The distributed CO2 storage is the small scale storage and its located near the emission areas. In the distributed CO2 storage, the CO2 is neutralized by sediment and underground water in the subsurface region (300-500m depth). Carbondioxide (CO2) included micro-nano bubbles is one approach in neutralizing CO2 and sediments by increasing CO2 volume per unit volume of water and accelerating the chemical reaction. In order to design underground treatment for CO2 gas in the subsurface, it is required to elucidate the behavior of CO2 included micro-nano bubbles in the water. In this study, we carried out laboratory experiment using the soil tank, and measure the amount of leakage of CO2 gas at the surface. In addition, the process of migration of carbondioxideincluded micro-nano bubble was monitored by the nondestructive method, wave velocity and resistivity.

The issue of global change is international in scope. A body of international organizations oversees the worldwide coordination of research and policy initiatives. In the US the National Science and Technology Council (NSTC) was established in November of 1993 to provide coordination of science, space, and technology policies throughout the federal government. NSTC is organized into nine proposed committees. The Committee on Environmental and Natural Resources (CERN) oversees the US Department of Energy`s Global Change Research Program (USGCRP). As part of the USGCRP, the US Department of Energy`s Global Change Research Program aims to improve the understanding of Earth systems and to strengthen the scientific basis for the evaluation of policy and government action in response to potential global environmental changes. This paper examines the information and data management roles of several international and national programs, including Oak Ridge National Laboratory`s (ORNL`s) global change information programs. An emphasis will be placed on the CarbonDioxide Information Analysis Center (CDIAC), which also serves as the World Data Center-A for Atmospheric Trace Gases.

A power plant includes a closed loop, supercritical carbondioxide system (CLS-CO.sub.2 system). The CLS-CO.sub.2 system includes a turbine-generator and a high temperature recuperator (HTR) that is arranged to receive expanded carbondioxide from the turbine-generator. The HTR includes a plurality of heat exchangers that define respective heat exchange areas. At least two of the heat exchangers have different heat exchange areas.

A method for geo-sequestration of a carbondioxideincludes selection of a target water-laden geological formation with low-permeability interbeds, providing an injection well into the formation and injecting supercritical carbondioxide (SC-CO.sub.2) and water or bine into the injection well under conditions of temperature, pressure and density selected to cause the fluid to enter the formation and splinter and/or form immobilized ganglia within the formation.

A process and apparatus for separating carbondioxide from gas, especially natural gas, that also contains C.sub.3+ hydrocarbons. The invention uses two or three membrane separation steps, optionally in conjunction with cooling/condensation under pressure, to yield a lighter, sweeter product natural gas stream, and/or a carbondioxide stream of reinjection quality and/or a natural gas liquids (NGL) stream.

The recycling of carbondioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the “Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

Global climate change is a serious environmental concern, and the US has developed ''An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the CarbonDioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's CarbonDioxide Research Program has been addressing the carbondioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the CarbonDioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a CarbonDioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbondioxide, and climate and vegetation change. One facet is the Core CO 2 Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO 2 concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration

Discusses the properties of carbondioxide in its solid "dry ice" stage. Suggests several demonstrations and experiments that use dry ice to illustrate Avogadro's Law, Boyle's Law, Kinetic-Molecular Theory, and the effects of dry ice in basic solution, in limewater, and in acetone. (TW)

Rising carbondioxide and global temperatures are causing increasing worldwide concern, and pressure towards an international law of the atmosphere is rapidly escalating, yet widespread misconceptions about the greenhouse effect's inevitability, time scale, and causes have inhibited effective consensus and action. Observations from Antarctic ice cores, Amazonian rain forests, and Carribean coral reefs suggest that the biological effects of climate change may be more severe than climate models predict. Efforts to limit emissions from fossil-fuel combustion alone are incapable of stabilizing levels of carbondioxide in the atmosphere. Stabilizing atmospheric carbondioxide requires coupled measures to balance sources and sinks of the gas, and will only be viable with large-scale investments in increased sustainable productivity on degraded tropical soils, and in long-term research on renewable energy and biomass product development in the developing countries. A mechanism is outlined which directly links fossil-fuel combustion sources of carbondioxide to removal via increasing biotic productivity and storage. A preliminary cost-benefit analysis suggests that such measures are very affordable, costing far less than inaction. (With 88 refs.).

Carbondioxide is a dangerous volcanic gas. When carbondioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbondioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbondioxide gas displaces oxygen as it collects in low-lying areas. When carbondioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

Solar carbondioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

The increasing atmospheric carbondioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbondioxide emissions is CO2 sequestration by mineral carbonation. The basic concept

Drawbacks of current carbondioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbondioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbondioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbondioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture.

Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The CarbonDioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the CarbonDioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

National Aeronautics and Space Administration — The Advanced Exploration Systems (AES) Life Support Systems project CarbonDioxide Removal and Management task includes development of systems that remove CO2 from a...

Global climate change is a serious environmental concern, and the US has developed An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the CarbonDioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's CarbonDioxide Research Program has been addressing the carbondioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the CarbonDioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a CarbonDioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbondioxide, and climate and vegetation change. One facet is the Core CO{sub 2} Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO{sub 2} concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration.

A method and apparatus to extract and sequester carbondioxide (CO2) from a stream or volume of gas wherein said method and apparatus hydrates CO2, and reacts the resulting carbonic acid with carbonate. Suitable carbonatesinclude, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO2 from a gaseous environment.

The author first highlights the reasons why storing carbondioxide in geological formations could be a solution in the struggle against global warming and climate change. Thus, he comments various evolutions and prospective data about carbon emissions or fossil energy consumption as well as various studies performed by international bodies and agencies which show the interest of carbondioxide storage. He comments the evolution of CO 2 contributions of different industrial sectors and activities, notably in France. He presents the different storage modes and methods which concern different geological formations (saline aquifers, abandoned oil or gas fields, not exploitable coal seams) and different processes (sorption, carbonation). He discusses the risks associated with these storages, the storable quantities, evokes some existing installations in different countries. He comments different ways to capture carbondioxide (in post-combustion, through oxy-combustion, by pre-combustion) and briefly evokes some existing installations. He evokes the issue of transport, and discusses efficiency and cost aspects, and finally has few words on legal aspects and social acceptability

This report is an overview on the subject of carbondioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbondioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbondioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbondioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting material is, however, highly desirable, because it is an inexpensive, non-toxic starting material. There are ongoing efforts to replace phosgene as a starting material. Creation of new materials and markets for them will increase this utilization, producing an increasingly positive, albeit small impact on global CO{sub 2} levels. The other uses of interest are utilization as a solvent and for fuel production and these will be discussed in turn.

Sodium based sorbents including sodium carbonate may be used to capture carbondioxide from flue gas. A relatively concentrated carbondioxide stream may be recoverable for sequestration when the sorbent is regenerated. Electrobalance tests indicated that sodium carbonate monohydrate was formed in a mixture of helium and water vapor at temperatures below 65 C. Additional compounds may also form, but this could not be confirmed. In the presence of carbondioxide and water vapor, both the initial reaction rate of sodium carbonate with carbondioxide and water and the sorbent capacity decreased with increasing temperature, consistent with the results from the previous quarter. Increasing the carbondioxide concentration at constant temperature and water vapor concentration produced a measurable increase in rate, as did increasing the water vapor concentration at constant carbondioxide concentration and temperature. Runs conducted with a flatter TGA pan resulted in a higher initial reaction rate, presumably due to improved gas-solid contact, but after a short time, there was no significant difference in the rates measured with the different pans. Analyses of kinetic data suggest that the surface of the sodium carbonate particles may be much hotter than the bulk gas due to the highly exothermic reaction with carbondioxide and water, and that the rate of heat removal from the particle may control the reaction rate. A material and energy balance was developed for a cyclic carbonation/calcination process which captures about 26 percent of the carbondioxide present in flue gas available at 250 C.

Fruitland coal and on activated carbon show that: (a) the Gibbs adsorption isotherm for CO{sub 2} under study exhibits typical adsorption behavior for supercritical gas adsorption, and (b) a slight variation from Type I absolute adsorption may be observed for CO{sub 2}, but the variation is sensitive to the estimates used for adsorbed phase density. (5) The experimental data were used to evaluate the predictive capabilities of various adsorption models, including the Langmuir/loading ratio correlation, a two-dimensional cubic equation of state (EOS), a new two-dimensional (2-D) segment-segment interactions equation of state, and the simplified local density model (SLD). Our model development efforts have focused on developing the 2-D analog to the Park-Gasem-Robinson (PGR) EOS and an improved form of the SLD model. The new PGR EOS offers two advantages: (a) it has a more accurate repulsive term, which is important for reliable adsorption predictions, and (b) it is a segment-segment interactions model, which should more closely describe the gas-coal interactions during the adsorption process. In addition, a slit form of the SLD model was refined to account more precisely for heterogeneity of the coal surface and matrix swelling. In general, all models performed well for the Type I adsorption exhibited by methane, nitrogen, and carbondioxide up to 8.3 MPa (average deviations within 2%). In comparison, the SLD model represented the adsorption behavior of all fluids considered within 5% average deviations, including the near-critical behavior of carbondioxide beyond 8.3 MPa (1200 psia). Work is in progress to (a) derive and implement the biporous form of the SLD model, which would expand the number of structural geometries used to represent the heterogeneity of coal surface; and (b) extend the SLD model to mixture predictions. (6) Proper reduction of our adsorption data requires accurate gas-phase compressibility (Z) factors for methane, ethane, nitrogen and carbondioxide

concentration. Most of the data given by the manufacturer relate to the gaseous concentration of combustible gaseous--such as hydrogen , carbon monoxide...UNCLASSIFIED * 15IS& OCASSIFICA TION/ OOWNGRADING N/A SCHEDULE 10. DISTRIBUTION STATEM tot dais Aspen ) Approved for public re-lease; distribution unlimited 17...were somewhat arbitrarily selected at + 0.1 -w Hg, which is a good goal for laboratory simulations , but this accuracy may not be reached in practical

This report summarises the work carried out at the ARE Physiological Laboratory (ARE(PL)) between July 1978 and December 1983. The work was intended to examine the proposition that some divers have a low ventilatory response to carbondioxide; that this results in a low ventilatory response to exercise with consequent hypercapnia; and that these characteristics put the diver at a greater-than-normal risk by increasing the individual`s susceptibility to oxygen toxicity and to other hazards associated with diving (e.g. nitrogen narcosis, decompression sickness and hypothermia). The specific aims of the project can be summarised as follows: (a) to demonstrate the existence of divers who exhibit the tendency to `retain carbondioxide` when working in hyperbaric conditions; (b) to define the circumstances under which such individuals are at risk; (c) to assess the magnitude of the risk; and (d) to recommend ways to eliminate or to reduce the risk. (author)

A slurried solid media for simultaneous water purification and carbondioxide removal from gas mixtures includes the steps of dissolving the gas mixture and carbondioxide in water providing a gas, carbondioxide, water mixture; adding a porous solid media to the gas, carbondioxide, water mixture forming a slurry of gas, carbondioxide, water, and porous solid media; heating the slurry of gas, carbondioxide, water, and porous solid media producing steam; and cooling the steam to produce purified water and carbondioxide.

The utilization of carbondioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbondioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbondioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbondioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbondioxide and direct synthesis of dimethyl carbonate from carbondioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbondioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity.

A paper describes a regenerable approach to separate carbondioxide from other cabin gases by means of cooling until the carbondioxide forms carbondioxide ice on the walls of the physical device. Currently, NASA space vehicles remove carbondioxide by reaction with lithium hydroxide (LiOH) or by adsorption to an amine, a zeolite, or other sorbent. Use of lithium hydroxide, though reliable and well-understood, requires significant mass for all but the shortest missions in the form of lithium hydroxide pellets, because the reaction of carbondioxide with lithium hydroxide is essentially irreversible. This approach is regenerable, uses less power than other historical approaches, and it is almost entirely passive, so it is more economical to operate and potentially maintenance- free for long-duration missions. In carbondioxide removal mode, this approach passes a bone-dry stream of crew cabin atmospheric gas through a metal channel in thermal contact with a radiator. The radiator is pointed to reject thermal loads only to space. Within the channel, the working stream is cooled to the sublimation temperature of carbondioxide at the prevailing cabin pressure, leading to formation of carbondioxide ice on the channel walls. After a prescribed time or accumulation of carbondioxide ice, for regeneration of the device, the channel is closed off from the crew cabin and the carbondioxide ice is sublimed and either vented to the environment or accumulated for recovery of oxygen in a fully regenerative life support system.

Air flow rates and carbondioxide concentrations of air entering and exiting eight H-Area waste tanks were monitored for a period of one year. The average instanteous concentration of carbondioxide in air is within the range reported offsite, and therefore is not affect by operation of the coal-fired power plant adjacent to the tank farm. Waste solutions in each of the tanks were observed to be continuously absorbing carbondioxide. The rate of absorption of carbondioxide decreased linearly with the pH of the solution. Personnel exposure associated with the routine sampling and analysis of radioactive wastes stored at SRP to determine the levels of corrosion inhibitors in solution could be reduced by monitoring the absorption of carbondioxide and using the relationship between pH and carbondioxide absorption to determine the free hydroxide concentration in solution

, when used in full scale animal buildings as basis for estimation of ventilation flow. Based on the data reviewed in this study, we recommend adding 10% carbondioxide production to the laboratory based carbondioxide production for animal houses with slatted or solid floors, provided that indoor manure......This article deals with carbondioxide production from farm animals; more specifically, it addresses the possibilities of using the measured carbondioxide concentration in animal houses as basis for estimation of ventilation flow (as the ventilation flow is a key parameter of aerial emissions from......C) has often been used. The article shows that the carbondioxide production per hpu increases with increasing respiration quotient. As the respiration quotient increases with body mass for growing animals, the carbondioxide production per heat production unit also increases with increased body mass...

Cometary and interstellar ices have carbondioxide to water mole ratios of up to 0.3. When melted, such high levels of carbondioxide cannot all be dissolved in the aqueous phase and instead partition into a CO2-rich (carbonic) fluid. This implies that during the accretion and formation of planetary systems carbonic fluids are not only possible, but common. In fact, they make up the atmosphere of Venus, are found bubbling out of Champagne Vent in the Pacific Ocean, and are documented by metamorphic fluid inclusions. Examination of phase diagrams reveals the conditions where carbonic fluids will exist or predominate. Carbonic fluids are predicted to exist in Earth's subduction zones and under the ice of small ocean worlds. CO2 had previously been shown to completely dissolve into NH­­3­-H­­2O oceans on small icy bodies by forming ammonium carbonate, but the newer measurements of CO2­ abundances indicate that not all of the CO2 can partition into the aqueous fluid as ammonium carbonate. The remaining CO2 would necessarily form a separate carbonic fluid making it likely that liquid CO2 would be a major oceanic component on some small icy bodies. The enhanced solubility of nonpolar and slightly polar organic compounds in carbonic fluids relative to aqueous fluids means that generation, transport, and deposition processes can be greatly enhanced in those cases where carbonic fluids occur. As an example, the solubility of benzoic acid, a polar compound, is about an order of magnitude greater in carbonic than in aqueous fluids, which is surprising given that water is a polar solvent and carbondioxide is a nonpolar solvent. Anthracene, a nonpolar compound, has an even greater solubility difference between carbonic and aqueous fluids at approximately four orders of magnitude. Highly polar compounds, including most of the building blocks of life, are more soluble in aqueous fluids than in carbonic fluids. The solubility difference of organic molecules in carbonic

Sonolysis of carbondioxide dissolved in water was performed from a standpoint of reducing this material in atmosphere. During one hour of sonication, the amount of CO2 decreased to about half at 5 degrees C under CO2-Ar atmosphere. The decreasing rate for CO2 followed the order Ar > He > H2 > N2 and it was down with increasing temperature in the range of 5-45 degrees C. The most favorable concentration for reducing CO2 was 0.03 (mole fraction of CO2 in gas phase). This concentration in gas phase means an equal mixture of CO2 and Ar in water, because CO2 is more soluble than Ar. Since carbondioxide dissolved in water would be partly ionized, the roles of ions on the sonolysis were also examined. Gaseous reaction products were CO, H2 and a small amount of O2. Carbon monoxide and hydrogen might be obtained from CO2 and H2O by sonolysis, respectively. Both gases are fuel and react each other to C1 compounds such as methanol, and so on. Therefore, irradiation of ultrasonic waves should be an important technique for reducing CO2.

Coal reserves can provide for the world`s energy needs for centuries. However, coal`s long term use may be severely curtailed if the emission of carbondioxide into the atmosphere is not eliminated. We present a safe and permanent method of carbondioxide disposal that is based on combining carbondioxide chemically with abundant raw materials to form stable carbonate minerals. We discuss the availability of raw materials and potential process designs. We consider our initial rough cost estimate of about 3{cents}/kWh encouraging. The availability of a carbondioxide fixation technology would serve as insurance in case global warming, or the perception of global warming, causes severe restrictions on carbondioxide emissions. If the increased energy demand of a growing world population is to be satisfied from coal, the implementation of such a technology would quite likely be unavoidable.

Cardox, the major supplier of carbondioxide, has developed a diffuser to introduce carbondioxide into a water volume as small bubbles to minimize reagent loss to the atmosphere. This unit is integral to several configurations suggested for treatment to control alkalinity in water streams.

Recent interest in atmospheric increases in carbondioxide have heightened the need for improved accuracy in measurements of fluxes of carbondioxide from soils. Diffusional movement has long been considered the dominant process by which trace gases move from the subsurface source to the surface, although there has been some indication that atmospheric pressure...

An electrocatalytic process for carbondioxide conversion includes combining a Catalytically Active Element and a Helper Polymer in the presence of carbondioxide, allowing a reaction to proceed to produce a reaction product, and applying electrical energy to said reaction to achieve electrochemical conversion of said carbondioxide reactant to said reaction product. The Catalytically Active Element can be a metal in the form of supported or unsupported particles or flakes with an average size between 0.6 nm and 100 nm. The reaction products comprise at least one of CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, (COO.sup.-).sub.2, and CF.sub.3COOH.

The authors' long-term goal is to develop accurate prediction methods for describing the adsorption behavior of gas mixtures on solid adsorbents over complete ranges of temperature, pressure, and adsorbent types. The originally-stated, major objectives of the current project are to: (1) measure the adsorption behavior of pure CO{sub 2}, methane, nitrogen, and their binary and ternary mixtures on several selected coals having different properties at temperatures and pressures applicable to the particular coals being studied, (2) generalize the adsorption results in terms of appropriate properties of the coals to facilitate estimation of adsorption behavior for coals other than those studied experimentally, (3) delineate the sensitivity of the competitive adsorption of CO{sub 2}, methane, and nitrogen to the specific characteristics of the coal on which they are adsorbed; establish the major differences (if any) in the nature of this competitive adsorption on different coals, and (4) test and/or develop theoretically-based mathematical models to represent accurately the adsorption behavior of mixtures of the type for which measurements are made. As this project developed, an important additional objective was added to the above original list. Namely, we were encouraged to interact with industry and/or governmental agencies to utilize our expertise to advance the state of the art in coalbed adsorption science and technology. As a result of this additional objective, we participated with the Department of Energy and industry in the measurement and analysis of adsorption behavior as part of two distinct investigations. These include (a) Advanced Resources International (ARI) DOE Project DE-FC26-00NT40924, ''Adsorption of Pure Methane, Nitrogen, and CarbonDioxide and Their Mixtures on Wet Tiffany Coal'', and (b) the DOE-NETL Project, ''Round Robin: CO{sub 2} Adsorption on Selected Coals''. These activities, contributing

The role of shelf seas in global carbon cycling is poorly understood. The dissolved inorganic carbon system and air-sea exchange of carbondioxide (CO2) are described for the Dutch coastal zone in September 1993. The inorganic carbon chemistry was affected by tidal mixing, wind speed, wind

A process to remove carbondioxide from a gas stream using a cross-flow, or a moving-bed reactor. In the reactor the gas contacts an active material that is an alkali-metal compound, such as an alkali-metal carbonate, alkali-metal oxide, or alkali-metal hydroxide; or in the alternative, an alkaline-earth metal compound, such as an alkaline-earth metal carbonate, alkaline-earth metal oxide, or alkaline-earth metal hydroxide. The active material can be used by itself or supported on a substrate of carbon, alumina, silica, titania or aluminosilicate. When the active material is an alkali-metal compound, the carbon-dioxide reacts with the metal compound to generate bicarbonate. When the active material is an alkaline-earth metal, the carbondioxide reacts with the metal compound to generate carbonate. Spent sorbent containing the bicarbonate or carbonate is moved to a second reactor where it is heated or treated with a reducing agent such as, natural gas, methane, carbon monoxide hydrogen, or a synthesis gas comprising of a combination of carbon monoxide and hydrogen. The heat or reducing agent releases carbondioxide gas and regenerates the active material for use as the sorbent material in the first reactor. New sorbent may be added to the regenerated sorbent prior to subsequent passes in the carbondioxide removal reactor.

Team C2CNT, or team Carbondioxide to carbon nanotubes, proprietary technology directly removes the widest range of carbondioxide from the ecosystem. C2CNT technology simply transforms low to high carbondioxide into carbon and oxygen, and the carbon produced is permanently removed, that is stable on the order of geologic time frames. C2CNT technology directly removes, transforms and stores atmospheric 0.04% CO2 without pre-concentration from the air, or 5% CO2 removal of gas power plant CO2...

Methods and compositions useful, for example, for physical solvent carbon capture. A method comprising: contacting at least one first composition comprising carbondioxide with at least one second composition to at least partially dissolve the carbondioxide of the first composition in the second composition, wherein the second composition comprises at least one siloxane compound which is covalently modified with at least one non-siloxane group comprising at least one heteroatom. Polydimethylsiloxane (PDMS) materials and ethylene-glycol based materials have high carbondioxide solubility but suffer from various problems. PDMS is hydrophobic but suffers from low selectivity. Ethylene-glycol based systems have good solubility and selectivity, but suffer from high affinity to water. Solvents were developed which keep the desired combinations of properties, and result in a simplified, overall process for carbondioxide removal from a mixed gas stream.

The CarbonDioxide Committee was given the task of preparing a suggestion of the acts aimed at reducing the greenhouse gas emissions and increasing the sinks of carbon in Finland. Emissions of all greenhouse gases were in 1990 80 million tons. calculated as carbondioxide. The carbondioxide emissions were about 58 million tons of the total. The increase of forest resources binds carbon from the atmosphere and reduces thereby net emissions of Finland at present by nearly 30 million tons of carbondioxide. Carbondioxide emissions will grow during the next decades, unless strong measures to control them will not be taken. As a result of the Commissions examination, acts will be needed both in the production of energy and in its consumption. Emissions can be reduced by replacing fossil fuels with nuclear energy, bioenergy and other renewable energy sources. Saving of energy and improvement of energy efficiency will limit carbondioxide emissions. The Commission has made suggestions both to change the structure of energy production and to control the consumption of energy. (orig.)

Factors controlling the capacity of the ocean for taking up anthropogenic C0 2 includecarbon chemistry, distribution of alkalinity, pCO 2 and total concentration of dissolved C0 2 , sea-air pCO 2 difference, gas exchange rate across the sea-air interface, biological carbon pump, ocean water circulation and mixing, and dissolution of carbonate in deep sea sediments. A general review of these processes is given and models of ocean-atmosphere system based on our understanding of these regulating processes axe used to estimate the magnitude of C0 2 uptake by the ocean. We conclude that the ocean can absorb up to 35% of the fossil fuel emission. Direct measurements show that 55% Of C0 2 from fossil fuel burning remains in the atmosphere. The remaining 10% is not accounted for by atmospheric increases and ocean uptake. In addition, it is estimated that an amount equivalent to 30% of recent annual fossil fuel emissions is released into the atmosphere as a result of deforestation and farming. To balance global carbon budget, a sizable carbon sink besides the ocean is needed. Storage of carbon in terrestrial biosphere as a result of C0 2 fertilization is a potential candidate for such missing carbon sinks

National Aeronautics and Space Administration — In this Phase I SBIR, Reactive Innovations, LLC (RIL) proposes to develop a compact and lightweight electrochemical to capture carbondioxide in the martian...

National Aeronautics and Space Administration — Reactive Innovations, LLC, proposes a Phase I SBIR program to develop a compact and lightweight electrochemical reactor to separate and pressurize carbondioxide...

Carbondioxide angiography is an established non-nephrotoxic option for imaging of the infradiaphragmatic arteries and veins. Safe performance of the technique once required a somewhat cumbersome system, however, recent innovations have simplified implementation and expanded the user base for this technique. As such, patient access has also increased. In this issue, Hameed et al. provide initial feasibility data regarding carbondioxide angiography and renal denervation therapy. This experience may be translated into future renovascular interventions in patients with limited renal reserve.

The DOE program focuses on three areas each of which requires more research before the many CO 2 -related questions can be answered. These areas include the global carbon cycle, climate effects, and vegetation effects. Additional information is needed to understand the sources and sinks of CO 2 . Research efforts include an attempt to estimate regional and global changes in temperature and precipitation. Increased atmospheric CO 2 may be a potential benefit to vegetation and crops because it is an essential element required for plant growth. Eight separate papers are included

Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbondioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbondioxide. The surfactant surrounded the droplet into carbondioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 {approx} 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbondioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbondioxide is then collected and reused. Thus, there are no secondary wastes. Carbondioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbondioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbondioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbondioxide. The surfactant surrounded the droplet into carbondioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 ∼ 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbondioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbondioxide is then collected and reused. Thus, there are no secondary wastes. Carbondioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbondioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

German utility RWE Power has initiated a cutting edge project that is investigating the use of marine microalgae to capture carbondioxide produced during lignite combustion. At its Niederaussem power plant, a pilot plant has been erected for the production of microalgae. Flue gas is withdrawn from the lignite-based power plant and transported through polyethylene pipes to the microalgae production plant. The CO{sub 2} in the flue gas is dissolved in the algae suspension and adsorbed by the algae for growth in photobioreactors, developed by Noragreen Projektmanagement GmbH. The photobioreactors which consist of clear plastic hoses, fixed in V shape to supports. The study is aiming to optimise the entire algae production process and subsequent conversion and use of the algae biomass produced. Uses being investigated include hydrothermal carbonization to obtain hydrocarbon products. 1 figs., 1 photo.

Our present dependence on fossil fuels means that, as our demand for energy inevitably increases, so do emissions of greenhouse gases, most notably carbondioxide (CO2). To avoid the obvious consequences on climate change, the concentration of such greenhouse gases in the atmosphere must be stabilized. But, as populations grow and economies develop, future demands now ensure that energy will be one of the defining issues of this century. This unique set of (coupled) challenges also means that science and engineering have a unique opportunity-and a burgeoning challenge-to apply their understanding to provide sustainable energy solutions. Integrated carbon capture and subsequent sequestration is generally advanced as the most promising option to tackle greenhouse gases in the short to medium term. Here, we provide a brief overview of an alternative mid- to long-term option, namely, the capture and conversion of CO2, to produce sustainable, synthetic hydrocarbon or carbonaceous fuels, most notably for transportation purposes. Basically, the approach centres on the concept of the large-scale re-use of CO2 released by human activity to produce synthetic fuels, and how this challenging approach could assume an important role in tackling the issue of global CO2 emissions. We highlight three possible strategies involving CO2 conversion by physico-chemical approaches: sustainable (or renewable) synthetic methanol, syngas production derived from flue gases from coal-, gas- or oil-fired electric power stations, and photochemical production of synthetic fuels. The use of CO2 to synthesize commodity chemicals is covered elsewhere (Arakawa et al. 2001 Chem. Rev. 101, 953-996); this review is focused on the possibilities for the conversion of CO2 to fuels. Although these three prototypical areas differ in their ultimate applications, the underpinning thermodynamic considerations centre on the conversion-and hence the utilization-of CO2. Here, we hope to illustrate that advances

It has been ascertained that heating titanium and tantalum in carbondioxide to temperatures of 500 or 800 0 C alters the composition of the gas phase, causing the advent of carbon monoxide and lowering the oxygen content. Investigation of the thermal stability of titanium polonides in a carbondioxide medium has shown that titanium mono- and hemipolonides are decomposed at temperatures below 350 0 C. The temperature dependence of the vapor pressure of polonium produced in the decomposition of these polonides in a carbondioxide medium have been determined by a radiotensimetric method. The enthalpy of the process, calculated from this relationship, is close to the enthalpy of vaporization of elementary polonium in vacuo

We devised an enzyme-based facilitated transport membrane bioreactor system to selectively remove carbondioxide (CO2) from the space station environment. We developed and expressed site-directed enzyme mutants for CO2 capture. Enzyme kinetics showed the mutants to be almost identical to the wild type save at higher pH. Both native enzyme and mutant enzymes were immobilized to different supports including nylons, glasses, sepharose, methacrylate, titanium and nickel. Mutant enzyme could be attached and removed from metal ligand supports and the supports reused at least five times. Membrane systems were constructed to test CO2 selectivity. These included proteic membranes, thin liquid films and enzyme-immobilized teflon membranes. Selectivity ratios of more than 200:1 were obtained for CO2 versus oxygen with CO2 at 0.1%. The data indicate that a membrane based bioreactor can be constructed which could bring CO2 levels close to Earth.

Provided herein are genetically engineered microbes that include at least a portion of a carbon fixation pathway, and in one embodiment, use molecular hydrogen to drive carbondioxide fixation. In one embodiment, the genetically engineered microbe is modified to convert acetyl CoA, molecular hydrogen, and carbondioxide to 3-hydroxypropionate, 4-hydroxybutyrate, acetyl CoA, or the combination thereof at levels greater than a control microbe. Other products may also be produced. Also provided herein are cell free compositions that convert acetyl CoA, molecular hydrogen, and carbondioxide to 3-hydroxypropionate, 4-hydroxybutyrate, acetyl CoA, or the combination thereof. Also provided herein are methods of using the genetically engineered microbes and the cell free compositions.

Upon electron irradiation the chemical composition was found to have altered and the new products from irradiation were found to be carbonyl sulphide (OCS), sulphur dioxide (SO2), ozone (O3), carbon trioxide (CO3), sulphur trioxide (SO3), carbon subsulphide (C3S2) and carbon monoxide (CO). Results obtained confirm ...

This report documents a rare case of carbondioxide intoxication in a young healthy male. The deceased hid in a small plastic container, size 1.5 x 1 x 1 m, and within 5 min he was located suffering convulsions and was reported as dead within minutes. Scene investigation revealed dry ice in the container. Autopsy findings were unremarkable. The probable cause of the convulsions was carbondioxide intoxication due to both the dry ice sublimation and the small confined space in which he was hiding. This report emphasizes the significance of scene investigation in establishing the cause of the death.

Photobiological hydrogen production is an alternative to thermochemical and electrolytic technologies with the advantage of carbondioxide sequestration. However, it suffers from low solar to hydrogen energy conversion efficiency due to limited light transfer, mass transfer, and nutrient medium composition. The present study aims at addressing these limitations and can be divided in three parts: (1) experimental measurements of the radiation characteristics of hydrogen producing and carbondioxide consuming microorganisms, (2) solar radiation transfer modeling and simulation in photobioreactors, and (3) parametric experiments of photobiological hydrogen production and carbondioxide sequestration. First, solar radiation transfer in photobioreactors containing microorganisms and bubbles was modeled using the radiative transport equation (RTE) and solved using the modified method of characteristics. The study concluded that Beer-Lambert's law gives inaccurate results and anisotropic scattering must be accounted for to predict the local irradiance inside a photobioreactor. The need for accurate measurement of the complete set of radiation characteristics of microorganisms was established. Then, experimental setup and analysis methods for measuring the complete set of radiation characteristics of microorganisms have been developed and successfully validated experimentally. A database of the radiation characteristics of representative microorganisms have been created including the cyanobacteria Anabaena variabilis, the purple non-sulfur bacteria Rhodobacter sphaeroides and the green algae Chlamydomonas reinhardtii along with its three genetically engineered strains. This enabled, for the first time, quantitative assessment of the effect of genetic engineering on the radiation characteristics of microorganisms. In addition, a parametric experimental study has been performed to model the growth, CO2 consumption, and H 2 production of Anabaena variabilis as functions of

A new method for the determination of sulfur forms in wine, i.e., free SO(2), total SO(2), bound SO(2), total S, and sulfate, is presented. The method is based on the measurement of the carbon monosulfide (CS) molecular absorption produced in a conventional air-acetylene flame using high-resolution continuum source absorption spectrometry. Individual sulfur forms can be distinguished because of the different sensitivities of the corresponding CS molecular absorption. The sensitivity of free SO(2) is about three times higher than the value for bound SO(2) and sulfate. The method makes use of procedures similar to those used in classic reference methods. Its performance is verified by analyzing six wine samples. Relative standard deviations are between 5 and 13% for free SO(2) and between 1 and 3% for total SO(2). For the validation of the accuracy of the new method, the results are compared with those of reference methods. The agreement of the values for total SO(2) with values of the classic method is satisfactory: five out of six samples show deviations less than 16%. Due to the instability of free SO(2) in wine and the known problems of the used reference method, serious deviations of the free SO(2) results are found for three samples. The evaluation of the limits of detection focuses on the value for free SO(2), which is the sulfur form having by far the lowest concentration in wine. Here, the achievable limit of detection is 1.8 mg L(-1). [figure: see text] Detection of non-metal elements using continuum source flame absorption spectrometry.

Performance testing of the International Space Station CarbonDioxide Removal Assembly flight hardware in the United States Laboratory during 1999 is described. The CDRA exceeded carbondioxide performance specifications and operated flawlessly. Data from this test is presented.

Magnesian calcite with controlled properties was synthesized for the removal of carbondioxide. The results from characterization, reactivity and CO{sub 2} capture capacity for different synthesis conditions are reported. The magnesian calcite samples (CaCO{sub 3}:MgCO{sub 3}) were synthesized by the coprecipitation of specific amounts of commercially available CaO and MgO by carbondioxide. Characterization was done with BET, SEM/EDS, particle size analysis and XRD. The capacity was measured using TGA cycles at 800 {sup o}C and compared for different preparation conditions. The effects of CaO, MgO and surfactant loading on the physical properties and carbonation activity were studied to determine the optimal synthesis condition. A long-term carbonation-calcination cycling test was conducted on the optimal sample. It was observed that the sample maintained its capacity to 86% of its original uptake even after 50 cycles.

A vertical photobioreactor containing the microalgae Scenedesmus obliquus is a highly efficient system for converting carbondioxide (CO2) into biomass. The use of photobioreactor for CO2 mitigation has been explored using microalgae as photosynthetic microorganism. The growth rate (m, h-1) were 0.03; 0.13; 0.20; 0.09 ...

Technological development from horse-drawn carriages to the new Airbus A380 has led to a remarkable increase in both the capacity and speed of tourist travel. This development has an endogenous systemic cause and will continue to increase carbondioxide emissions/energy consumption if left

Oct 17, 2011 ... CSD can be used to gain information related to CO2 fixing microbes. It can also contribute to devising biological strategies for reducing carbondioxide from the environment. It introduces an innovative idea of exploring the potential of these bacterial strains for reversing global warming. The CSD can be.

This thesis presents new insights into the reduction of carbondioxide to methane and ethylene on copper electrodes. This electrochemical process has great potential for the storage of surplus renewable electrical energy in the form of hydrocarbons. The research described in this thesis focuses on

Heat transfer coefficient and pressure drop for boiling carbondioxide (R744) flowing in a horizontal pipe has been measured. The pipe is heated by condensing R22 outside the pipe. The heat input is supplied by an electrical heater wich evaporates the R22. With the heat flux assumed constant over...

Heat transfer coefficient and pressure drop for boiling carbondioxide (R744) flowing in a horizontal pipe has been measured. The calculated heat transfer coeeficient has been compared with the Chart correlation of Shah. The Chart Correlation predits too low heat transfer coefficient but the ratio...

Carbondioxide (CO2) is one of the most important greenhouse gases (GHG). The most dominant source of anthropogenic CO2 contributing to the rise in atmospheric concentration since the industrial revolution is the combustion of fossil fuels. These emissions are expected to result in global climate

The use of polyaniline and especially sulfonated polyaniline (SPAN) is explored for sensing carbondioxide (CO2) at room temperature. Frequency-dependent AC measurements were carried out to detect changes in impedance of the polymer, drop casted on interdigitated electrodes, when exposed to CO2 gas.

We investigate the physical foaming process of glassy poly(ether imide) and poly(ether sulfone) using carbondioxide and report temperature-concentration diagrams ("foam diagrams") marking out the foaming envelope in which dense CO2-saturated films expand and microvoids are introduced. Two types of

emulsions with a flow through, static mixer based apparatus under a variety of conditions that are suitable for permanent sequestration of carbondioxide. A variety of mixtures of water, CO{sub 2} and particles may also provide suitable emulsions capable of PS. In addition, it is necessary to test the robustness of PSE formation as composition changes to be certain that emulsions of appropriate size and stability form under conditions that might vary during actual large scale EOR and sequestration operations. The goal was to lay the groundwork for an apparatus and formulation that would produce homogenous microemulsions of CO{sub 2}-in-water capable of readily mixing with the waters of deep saline aquifers and allow a safer and more permanent sequestration of carbondioxide. In addition, as a beneficial use, we hoped to produce homogenous microemulsions of water-in-CO{sub 2} capable of readily mixing with pure liquid or supercritical CO{sub 2} for use in Enhanced Oil Recovery (EOR). However, true homogeneous microemulsions have proven very difficult to produce and efforts have not yielded either a formulation or a mixing strategy that gives emulsions that do not settle out or that can be diluted with the continuous phase in varying proportions. Other mixtures of water, CO{sub 2} and particles, that are not technically homogeneous microemulsions, may also provide suitable emulsions capable of PS and EOR. For example, a homogeneous emulsion that is not a microemulsion might also provide all of the necessary characteristics desired. These characteristics would include easy formation, stability over time, appropriate size and the potential for mineralization under conditions that would be encountered under actual large scale sequestration operations. This report also describes work with surrogate systems in order to test conditions.

To obtain prediction data on the change in properties of titaniumand vanadium-base powder metallurgy materials operating in a carbondioxide atmosphere, and also to clarify the mechanism of their interaction with the gas in this work, gravimetric investigations of specimens heated at temperatures of 300-1000 C and an x-ray diffraction analysis of their surface were made and the composition of the gas in the heating chamber was studied. The results of the investigations indicate a similarity between the mechanisms of interaction of titanium and vanadium with carbondioxideincluding the formation of oxides on the surface of the metal with subsequent carbidization at temperatures above 800 C. On the basis of the data obtained, it may be concluded that the operating temperature limits of titanium- or vanadium-base materials in carbondioxide must not exceed 400 and 600 C, respectively

Full Text Available The solid fuel gasification process was investigated to define chemical reactions rate and activation energy for a gas-generator designing and regime optimizing. An experimental procedure includes coal char samples of Kuznetskiy and Kansko-Achinskiy deposits consequent argon pyrolysis into argon and oxidating into carbondioxide with different temperatures. The thermogravimetric analysis data of coal char gasification into carbondioxide was obtained in the temperature range 900–1200 ºC. The mass loss and gasification time dependencies from temperature were defined to calculate chemical reaction frequency factor and activation energy. Two coal char gasification physico-mathematical models were proposed and recommendations for them were formed.

A simulation model of international tourist flows is used to estimate the impact of includingcarbondioxide emissions from aviation fuels in the European Trading System. The effect on global carbondioxide emissions from international aviation is minimal: -0.01% at current permit prices, and ?0.13% for the aggressive climate policy advocated by the Stern Review. In the latter case, total CO2 emissions from fossil fuels would fall by 0.004%, and total greenhouse gas emissions by 0.002%. Touri...

This project is aimed at demonstrating technical feasibility for a lithium zirconate based dense ceramic membrane for separation of carbondioxide from flue gas at high temperature. The research work conducted in this reporting period was focused on several fundamental issues of lithium zirconate important to the development of the dense inorganic membrane. These fundamental issues include material synthesis of lithium zirconate, phases and microstructure of lithium zirconate and structure change of lithium zirconate during sorption/desorption process. The results show difficulty to prepare the dense ceramic membrane from pure lithium zirconate, but indicate a possibility to prepare the dense inorganic membrane for carbondioxide separation from a composite lithium zirconate

Supercritical CO2 can be injected into deep saline aquifers to reduce the amount of CO2 in the atmosphere and thus, lessen the impact on the global warming. Qualified reservoirs should be in a sufficient depth to guarantee the thermodynamical environment for the supercritical state of CO2. Furthermore, an impermeable cap-rock layer must confine the reservoir layer, in order to collect the CO2 in the desired region. In CO2 storage it is crucial to guarantee the safety of the storage site and to eliminate possibilities of leakage. Therefore, deformation processes of the rock matrix and the cap-rock layer, which might be induced by the high pressure injection of CO2, must be investigated. The increase in stress may also cause crack development in the cap-rock layer. These could either be new developing fractures or the break-up of already existing but cemented cracks or faults. If such cracks occur, CO2 could migrate to shallower regions where the temperature and pressure cannot support the supercritical condition of the CO2 anymore. Thus, it is important to describe the phase transition process between supercritical, liquid and gaseous CO2. This requires a proper understanding of the thermodynamical behaviour of CO2 within the reservoir. The Theory of Porous Media (TPM) provides a useful continuum-mechanical basis to describe real natural systems in a thermodynamically consistent way. Hence, the TPM is applied to model multiphasic flow of CO2 and water and include elasto-plastic solid deformations of the porous matrix. The Peng-Robinson equation is implemented as a cubic equation of state to describe the phase behaviour of CO2 in the liquid, gaseous and supercritical region. However, in the two-phase region the isotherms show a horizontal section and kinks at the boiling and vapour curve. This cannot be represented by a continuously differentiable function such as the Peng-Robinson equation. To circumvent this problem, the Antoine equation provides additional

A two-step resin recycling system and method solvent that produces essentially contaminant-free synthetic resin material. The system and method includes one or more solvent wash vessels to expose resin particles to a solvent, the solvent contacting the resin particles in the one or more solvent wash vessels to substantially remove contaminants on the resin particles. A separator is provided to separate the solvent from the resin particles after removal from the one or more solvent wash vessels. The resin particles are next exposed to carbondioxide in a closed loop carbondioxide system. The closed loop system includes a carbondioxide vessel where the carbondioxide is exposed to the resin, substantially removing any residual solvent remaining on the resin particles after separation. A separation vessel is also provided to separate the solvent from the solvent laden carbondioxide. Both the carbondioxide and the solvent are reused after separation in the separation vessel.

Papers presented at the CarbonDioxide and Climate Research Program Conference are included in this volume. Topics discussed are: the carbon cycle; modeling the carbon system; climatic response due to increased CO2; climate modeling; the use of paleoclimatic data in understanding climate change; attitudes and implications of CO2; social responses to the CO2 problem; a scenario for atmospheric CO2 to 2025; marine photosynthesis and the global carbon cycle; and the role of tropical forests in the carbon balance of the world. Separate abstracts of nine papers have been prepared for inclusion in the Energy Data Base. (RJC)

In the year 2013, 9.5 billion metric tons of carbondioxide gas was emitted into the air, and each year this amount is increasing [1]. Carbondioxide emissions are of particular concern as they represent 80% of greenhouse gas emissions and therefore are a large contributor to global warming. Amon...... framework with its implemented methods and tools is a small but important step. Collaboration and integration of data, methods and tools is necessary to provide a more sustainable solution to the global carbondioxide emission problem.......In the year 2013, 9.5 billion metric tons of carbondioxide gas was emitted into the air, and each year this amount is increasing [1]. Carbondioxide emissions are of particular concern as they represent 80% of greenhouse gas emissions and therefore are a large contributor to global warming. Among...... which the issue of global carbondioxide emissions can be investigated in terms of different available capture-utilization technologies, solution methods, and benefit scenarios, with the objective to determine more sustainable solutions within an appropriate application boundary. The framework would...

Carbondioxide (CO 2 ), a key greenhouse gas produced from both anthropogenic and natural sources, has been recently considered to be an important C1 building-block for the synthesis of many industrial fuels and chemicals. Catalytic hydrogenation of CO 2 using a homogeneous system is regarded as an efficient process for CO 2 valorization. This approach leads to the direct products including formic acid (HCOOH), carbon monoxide (CO), methanol (MeOH), and methane (CH 4 ). The hydrogenation of CO 2 to CO followed by alkene carbonylation provides value-added compounds, which also avoids the tedious separation and transportation of toxic CO. Moreover, the reduction of CO 2 with H 2 in the presence of amines is of significance to attain fine chemicals through catalytic formylation and methylation reactions. The synthesis of higher alcohols and dialkoxymethane from CO 2 and H 2 has been demonstrated recently, which opens access to new molecular structures using CO 2 as an important C1 source.

The carbondioxide laser has been used to treat various lesions of the head and neck, ranging from carcinomas to hemangiomas, and even including tatoos. A search of the literature does not reveal any reports of the carbondioxide laser being used to treat lymphangioma. This report discusses the efficacy of treating lymphangioma of the air and food passages with the carbondioxide laser, and presents three patients who have been treated in this fashion-two for palliation and one for cure.

This paper reviews issues and applications for design of sustainable carbondioxide conversion processes, specifically through chemical conversion, and the integration of the conversion processes with other systems from a process systems engineering (PSE) view-point. Systematic and computer...... conversion processes with other systems including coexisting infrastructure and carbondioxide sources is described.Then, the importance of PSE based studies for such application is discussed. Finally, some perspectives on the status and future directions of carbondioxide conversion technology...

Measurement of the arterial carbondioxide (P(a)CO(2)) is an established part of the monitoring of mechanically ventilated patients. Other ways to get information about carbondioxide in the patient are measurement of end-tidal carbondioxide (P(ET)CO(2)) and transcutaneous carbondioxide (PTCCO2......). Carbondioxide in the blood and cerebral tissue has great influence on vasoactivity and thereby blood volume of the brain. We have found no studies on the correlation between P(ET)CO(2) or P(TC)CO(2), and P(a)CO(2) during hyperbaric oxygen therapy (HBOT)....

A process for removing carbondioxide from a carbondioxide-loaded solvent uses two stages of flash apparatus. Carbondioxide is flashed from the solvent at a higher temperature and pressure in the first stage, and a lower temperature and pressure in the second stage, and is fed to a multi-stage compression train for high pressure liquefaction. Because some of the carbondioxide fed to the compression train is already under pressure, less energy is required to further compress the carbondioxide to a liquid state, compared to conventional processes.

With the rapid development of global economy, human beings have become highly dependent upon fossil fuel such as coal and petroleum. Much fossil fuel is consumed in industrial production and human life. As a result, carbondioxide emissions have been increasing, and the greenhouse effects thereby generated are posing serious threats to environment of the earth. These years, increasing average global temperature, frequent extreme weather events and climatic changes cause material disasters to the world. After scientists’ long-term research, ample evidences have proven that emissions of greenhouse gas like carbondioxide have brought about tremendous changes to global climate. To really reduce carbondioxide emissions, governments of different countries and international organizations have invested much money and human resources in performing research related to carbondioxide emissions. Manual underground carbondioxide storage and carbondioxide-enhanced oil recovery are schemes with great potential and prospect for reducing carbondioxide emissions. Compared with other schemes for reducing carbondioxide emissions, aforementioned two schemes exhibit high storage capacity and yield considerable economic benefits, so they have become research focuses for reducing carbondioxide emissions. This paper introduces the research progress in underground carbondioxide storage and enhanced oil recovery, pointing out the significance and necessity of carbondioxide-driven enhanced oil recovery.

The increasing carbon footprint of the water and organic waste sectors has led to water utilities to voluntarily includecarbon mitigation approaches within their strategic plans and to an increase in research aimed at mitigating carbondioxide (CO2) emissions. Injection of CO2 in anaerobic digesters (ADs) for its bioconversion into methane (CH4) has been identified as a potential solution. However, previous literature provided limited knowledge of the carbon benefits obtainable and presented...

The off gas produced by reprocessing spent nuclear fuel includes various radioactivities and these nuclei should be removed. In particular, 14 C mainly released as the form of carbondioxide is one of the most required gaseous radioactivities to be removed because it has long a half-life. One of the methods to remove gaseous nuclei is the use of adsorption technique. The off gas contains water vapor which influences adsorption process of carbondioxide. In this report, behavior of adsorption of carbondioxide on various adsorbent and influence on adsorption behavior of carbondioxide by containing water vapor are discussed. (author)

The stability of biochar in soil is of importance if it is to be used for carbon sequestration and long-term improvement of soil properties. It is well known that a significant fraction of biochar is highly stable in soil, but carbondioxide (CO2) is also released immediately after application....... This study investigated the nature of the early release of CO2 and the degree to which stabilizing mechanisms protect biochar from microbial attack. Incubations of 14C-labelled biochar produced at different temperatures were performed in soils with different clay contents and in sterilized and non......-sterilized soils. It emerged that carbonate may be concentrated or form during or after biochar production, resulting in significant carbonate contents. If CO2 released from carbonates in short-term experiments is misinterpreted as mineralization of biochar, the impact of this process may be significantly over...

In recent years, several studies about electrical discharge plasma in supercritical carbondioxide (CO2) have been carried out. One of the unique characteristics of supercritical fluid is a large density fluctuation near the critical point that can result in marked dramatic changes of thermal conductivity. Therefore, the electrical discharge plasma produced in supercritical fluid has unique features and reactions unlike those of normal plasma produced in gas phase. In our experiments, two typ...

A three year research project was presented that would define the role of the Arctic ocean, sea ice, tundra, taiga, high latitude ponds and lakes and polar anthropogenic activity on the carbondioxide content of the atmosphere. Due to the large physical and geographical differences between the two polar regions, a comparison of CO/sub 2/ source and sink strengths of the two areas was proposed. Research opportunities during the first year, particularly those aboard the Swedish icebreaker, YMER, provided additional confirmatory data about the natural source and sink strengths for carbondioxide in the Arctic regions. As a result, the hypothesis that these natural sources and sinks are strong enough to significantly affect global atmospheric carbondioxide levels is considerably strengthened. Based on the available data we calculate that the whole Arctic region is a net annual sink for about 1.1 x 10/sup 15/ g of CO/sub 2/, or the equivalent of about 5% of the annual anthropogenic input into the atmosphere. For the second year of this research effort, research on the seasonal sources and sinks of CO/sub 2/ in the Arctic will be continued. Particular attention will be paid to the seasonal sea ice zones during the freeze and thaw periods, and the tundra-taiga regions, also during the freeze and thaw periods.

Full Text Available Bariatric restrictive and malabsorptive operations are being carried out in most countries laparoscopically. Carbondioxide or gas embolism has never been reported in obese patients undergoing bariatric surgery. We report a case of carbondioxide embolism during laparoscopic sleeve gastrectomy (LSG in a young super obese female patient. Early diagnosis and successful management of this complication are discussed. An 18-year-old super obese female patient with enlarged fatty liver underwent LSG under general anesthesia. During initial intra-peritoneal insufflation with CO 2 at high flows through upper left quadrant of the abdomen, she had precipitous fall of end-tidal CO 2 and SaO 2 % accompanied with tachycardia. Early suspicion led to stoppage of further insufflation. Clinical parameters were stabilized after almost 30 min, while the blood gas analysis was restored to normal levels after 1 h. The area of gas entrainment on the damaged liver was recognized by the surgeon and sealed and the surgery was successfully carried out uneventfully. Like any other laparoscopic surgery, carbondioxide embolism can occur during bariatric laparoscopic surgery also. Caution should be exercised when Veress needle is inserted through upper left quadrant of the abdomen in patients with enlarged liver. A high degree of suspicion and prompt collaboration between the surgeon and anesthetist can lead to complete recovery from this potentially fatal complication.

Scientists can now propagate healthy blueberry and raspberry plants from virus-infected stock by treating it with heat and carbondioxide. Plants are grown at 100/sup 0/F, which makes them develop faster than the virus can spread. Then cuttings are taken of the new growth - less than an inch long - and grown into full-sized, virus-free plants. But in this race to outdistance the virus, some plant species are not able to take the heat. Some even die. Chemical reactions double for every 14/sup 0/F rise in temperature. So, if you try to grow a plant at 100/sup 0/F that was originally growing at 86/sup 0/F, it will double its respiration rate. Adding carbondioxide increases the rate of photosynthesis in plants, which increases the plant's food reserves. What carbondioxide does to allow some plants to grow at temperatures at which they would otherwise not survive and it allows other plants to grow for longer periods at 100/sup 0/F. One problem with the process, says Converse, is that the longer plants are exposed to heat the greater the mutation rate. So, resulting clones should be closely examined for trueness to horticultural type.

An electrochemical cell comprising a novel dual-component graphite and Earth-crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbondioxide mineralisation. Under an atmosphere of 5 % carbondioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbondioxide into aqueous solution as hydrogen carbon...

The two-step syntheses of the cyclic carbonatescarbonated methyl oleate (CMO) and carbonated methyl linoleate (CML) are reported. First, synthesis of epoxides through well-precedented chemical reactions of unsaturated fatty methyl esters with hydrogen peroxide and formic acid was accomplished. Next, a carbonation reaction with a simple tetrabutylammonium bromide catalyst was performed, allowing the direct incorporation of carbondioxide into the oleochemical. These syntheses avoid the use of the environmentally unfriendly phosgene. The carbonated products are characterized by IR, 1H NMR, and 13C NMR spectroscopy and studied by thermogravimetric analysis (TGA). Also reported is the synthesis of a similar cyclic carbonate from the commercially available 2-ethylhexyl epoxy soyate. These carbonates show properties that may make them useful as petrochemical replacements or as biobased industrial product precursors.

This invention comprises a method for rapidly and continuously immobilizing carbondioxide contained in various industrial off-gas streams, the carbondioxide being immobilized as dry, stable, and substantially water-insoluble particulates. Briefly, the method comprises passing the gas stream through a fixed or fluidized bed of hydrated barium hydroxide to remove and immobilize the carbondioxide by converting the bed to barium carbonate. The method has several important advantages: it can be conducted effectively at ambient temperature; it provides a very rapid reaction rate over a wide range of carbondioxide concentrations; it provides high decontamination factors; and it has a high capacity for carbondioxide. The invention is especially well suited for the removal of radioactive carbondioxide from off-gases generated by nuclear-fuel reprocessing facilities and nuclear power plants

For long-term human missions, a closed-loop atmosphere revitalization system (ARS) is essential to minimize consumables. A carbondioxide (CO2) reduction technology is used to reclaim oxygen (O2) from metabolic CO2 and is vital to reduce the delivery mass of metabolic O2. A key step in closing the loop for ARS will include a proper CO2 reduction subsystem that is reliable and with low equivalent system mass (ESM). Sabatier and Bosch CO2 reduction are two traditional CO2 reduction subsystems (CRS). Although a Sabatier CRS has been delivered to International Space Station (ISS) and is an important step toward closing the ISS ARS loop, it recovers only 50% of the available O2 in CO2. A Bosch CRS is able to reclaim all O2 in CO2. However, due to continuous carbon deposition on the catalyst surface, the penalties of replacing spent catalysts and reactors and crew time in a Bosch CRS are significant. Recently, technologies have been developed for recovering hydrogen (H2) from Sabatier-product methane (CH4). These include methane pyrolysis using a microwave plasma, catalytic thermal pyrolysis of CH4 and thermal pyrolysis of CH4. Further, development in Sabatier reactor designs based on microchannel and microlith technology could open up opportunities in reducing system mass and enhancing system control. Improvements in Bosch CRS conversion have also been reported. In addition, co-electrolysis of steam and CO2 is a new technology that integrates oxygen generation and CO2 reduction functions in a single system. A co-electrolysis unit followed by either a Sabatier or a carbon formation reactor based on Bosch chemistry could improve the overall competitiveness of an integrated O2 generation and CO2 reduction subsystem. This study evaluates all these CO2 reduction technologies, conducts water mass balances for required external supply of water for 1-, 5- and 10-yr missions, evaluates mass, volume, power, cooling and resupply requirements of various technologies. A system

Carbondioxide in the air may be increasing because the world is warming. This possibility, which contradicts the hypothesis of an enhanced greenhouse warming driven by manmade emissions, is here pursued in two ways. First, increments in carbondioxide are treated as readings of a natural thermometer that tracks global and hemispheric temperature deviations, as gauged by meteorologists' thermometers. Calibration of the carbondioxide thermometer to conventional temperatures then leads to a history of carbondioxide since 1856 that diverges from the ice-core record. Secondly, the increments of carbondioxide can also be accounted for, without reference to temperature, by the combined effects of cosmic rays, El Nino and volcanoes. The most durable effect is due to cosmic rays. A solar wind history, used as a long-term proxy for the cosmic rays, gives a carbondioxide history similar to that inferred from the global temperature deviations. (author)

Nuclear energy has been developed as a major source of electric power in Canada. Electricity from nuclear energy already avoids the emission of about 100 million tonnes of carbondioxide to the atmosphere in Canada. This is a significant fraction of the 619 million tonnes of Canadian greenhouse gas emissions in 1995. However, the current scope of application of electricity to end use energy needs in Canada limits the contribution nuclear energy can make to carbondioxide emission reduction. Nuclear energy can also contribute to carbondioxide emissions reduction through expansion of the use of electricity to less traditional applications. Transportation, in particular contributed 165 million tonnes of carbondioxide to the Canadian atmosphere in 1995. Canada's fleet of personal vehicles consisted of 16.9 million cars and light trucks. These vehicles were driven on average 21,000 km/year and generated 91 million tonnes of greenhouse gases expressed as a C02 equivalent. Technology to improve the efficiency of cars is under development which is expected to increase the energy efficiency from the 1995 level of about 10 litres/100 km of gasoline to under 3 litres/100km expressed as an equivalent referenced to the energy content of gasoline. The development of this technology, which may ultimately lead to the practical implementation of hydrogen as a portable source of energy for transportation is reviewed. Fuel supply life cycle greenhouse gas releases for several personal vehicle energy supply systems are then estimated. Very substantial reductions of greenhouse gas emissions are possible due to efficiency improvements and changing to less carbon intensive fuels such as natural gas. C02 emissions from on board natural gas fueled versions of hybrid electric cars would be decreased to approximately 25 million t/year from the current 91 million tonnes/year. The ultimate reduction identified is through the use of hydrogen fuel produced via electricity from CANDU power

Experimental and theoretical studies on the interaction of carbondioxide with pseudomorphic and rough copper layers deposited on a platinum (111) single crystal are reported. Evidence for carbondioxide dissociation and carbonate formation is presented and the relevance to methanol synthesis...

Hyperkalaemia with ECG changes had been noted during prolonged carbondioxide pneumoperitoneum in pigs. We have compared plasma potassium concentrations during surgery in 11 patients allocated randomly to undergo either laparoscopic or open appendectomy and in another 17 patients allocated randomly...... to either carbondioxide pneumoperitoneum or abdominal wall lifting for laparoscopic colectomy. Despite an increasing metabolic acidosis, prolonged carbondioxide pneumoperitoneum resulted in only a slight increase in plasma potassium concentrations, which was both statistically and clinically insignificant...

Abstract An electrochemical cell comprising a novel dual‐component graphite and Earth‐crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbondioxide mineralisation. Under an atmosphere of 5 % carbondioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbondioxide into aqueous solution as hydrog...

Full Text Available Supercritical carbondioxide (scCO2 could be one aspect of a significant and necessary movement towards green chemistry, being a potential replacement for volatile organic compounds (VOCs. Unfortunately, carbondioxide has a notoriously poor solubilising power and is famously difficult to handle. This review examines attempts and breakthroughs in enhancing the physicochemical properties of carbondioxide, focusing primarily on factors that impact solubility of polar and ionic species and attempts to enhance scCO2 viscosity.

This study aims to determine the effects of the automotive industry on carbondioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbondioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbondioxide emissions in France, Sweden, Spain, Hungary and Japa...

The reaction between titanium polonides and carbondioxide has been studied by comparing titanium polonide thermal resistance in vacuum and in carbondioxide. The investigation has shown that titanium mono- and semipolonides fail at temperatures below 350 deg C. Temperature dependence of polonium vapor pressure prepared at failure of the given polonides is determined by the radiotensiometry in carbondioxide. Enthalpy calculated for this dependence is close to the enthalpy of elementary polonium evaporation in vacuum

This thesis examined the process that affects the exchange of carbon between the soil and the atmosphere with particular attention to the large amounts of carbon stored in soils in the form of decaying organic matter. This forest floor measuring study was conducted in 2000 at a micro-meteorological tower flux site in a coastal temperature Douglas-fir forest. The measuring study involved half hourly measurements of both carbondioxide and below-ground carbondioxide storage. Measurements were taken at 6 locations between April and December to include a large portion of the growing season. Eddy covariance (EC) measurements of carbondioxide flux above the forest floor over a two month period in the summer and the autumn were compared with forest floor measurements. Below-ground carbondioxide mixing ratios of soil air were measured at 6 depths between 0.02 to 1 m using gas diffusion probes and a syringe sampling method. Maximum carbondioxide fluxes measured by the soil chambers varied by a factor of 3 and a high spatial variability in soil carbondioxide flux was noted. Forest floor carbondioxide fluxes measured by each of the chambers indicated different sensitivities to soil temperature. Hysteresis in the flux temperature relationship over the year was evident. Reliable below-canopy EC measurements of the forest floor carbondioxide flux were difficult to obtain because of the every low wind speeds below the forest canopy. The amount of carbon dioxde present in the soil increased rapidly with depth near the surface but less rapidly deeper in the soil. It was suggested that approximately half of the carbondioxide produced below-ground comes from between the soil surface and the first 0.15 m of depth. Carbondioxide fluxes from the floor of a Douglas-fir forest were found to be large compared to other, less productive ecosystems

Hyperkalaemia with ECG changes had been noted during prolonged carbondioxide pneumoperitoneum in pigs. We have compared plasma potassium concentrations during surgery in 11 patients allocated randomly to undergo either laparoscopic or open appendectomy and in another 17 patients allocated randomly...... to either carbondioxide pneumoperitoneum or abdominal wall lifting for laparoscopic colectomy. Despite an increasing metabolic acidosis, prolonged carbondioxide pneumoperitoneum resulted in only a slight increase in plasma potassium concentrations, which was both statistically and clinically insignificant....... Thus hyperkalaemia is unlikely to develop in patients with normal renal function undergoing carbondioxide pneumoperitoneum for laparoscopic surgery....

National Aeronautics and Space Administration — The results of published and unpublished experiments investigating the impacts of elevated carbondioxide on the chemistry (nitrogen and lignin concentration) of...

National Aeronautics and Space Administration — ABSTRACT: The results of published and unpublished experiments investigating the impacts of elevated carbondioxide on the chemistry (nitrogen and lignin...

In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbondioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbondioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbondioxide to form an adduct with carbondioxide.

In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbondioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbondioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbondioxide to form an adduct with carbondioxide.

A composition, process and system for capturing carbondioxide from a combustion gas stream. The composition has a particulate porous support medium that has a high volume of pores, an alkaline component distributed within the pores and on the surface of the support medium, and water adsorbed on the alkaline component, wherein the proportion of water in the composition is between about 5% and about 35% by weight of the composition. The process and system contemplates contacting the sorbent and the flowing gas stream together at a temperature and for a time such that some water remains adsorbed in the alkaline component when the contact of the sorbent with the flowing gas ceases.

This road-map proposes by the Group Total aims to inform the public on the carbondioxide capture and geological storage. One possible means of climate change mitigation consists of storing the CO 2 generated by the greenhouse gases emission in order to stabilize atmospheric concentrations. This sheet presents the CO 2 capture from lage fossil-fueled combustion installations, the three capture techniques and the CO 2 transport options, the geological storage of the CO 2 and Total commitments in the domain. (A.L.B.)

A lot of experts propose to dispose of the Co2 in the Oceans; but there is some confusion on that subject. The possibility of dispersing the CarbonDioxide on the Ocean floor must be considered with great caution, carefully studying all the possible balances Co2 is subject to. A parameter which must be considered is the possibility for Co2 - whatever the form may be - of solving in the sea water, even when very deep. At the moment, the most safe way of storing the Co2 in the oceans seems to be the introduction of Co2 Hydrates into the sediments under the ocean floor [it

This article is devoted to nuclear energy, to its acceptability, compatibility and sustainability. Nuclear energy is non-dispensable part of energy sources with vast innovation potential. The safety of nuclear energy, radioactive waste deposition, and prevention of risk from misuse of nuclear material have to be very seriously adjudged and solved. Nuclear energy is one of the ways how to decrease the contamination of atmosphere with carbondioxide and it solves partially also the problem of global increase of temperature and climate changes. Given are the main factors responsible for the renaissance of nuclear energy. (author)

Recent scientific studies are rapidly advancing novel technological improvements and engineering developments that demonstrate the ability to minimize, eliminate, or facilitate the removal of various contaminants and green house gas emissions in power generation. The Integrated Gasification Combined Cycle (IGCC) shows promise for carbondioxide mitigation not only because of its higher efficiency as compared to conventional coal firing plants, but also due to a higher driving force in the form of high partial pressure. One of the novel technological concepts currently being developed and investigated is membranes for carbondioxide (CO2) separation, due to simplicity and ease of scaling. A challenge in using membranes for CO2 capture in IGCC is the possibility of failure at elevated temperatures or pressures. Our earlier research studies examined the use of ionic liquids on various supports for CO2 separation over the temperature range, 37°C-300°C. The ionic liquid, 1-hexyl-3methylimidazolium Bis(trifluoromethylsulfonyl)imide, ([hmim][Tf2N]), was chosen for our initial studies with the following supports: polysulfone (PSF), poly(ether sulfone) (PES), and cross-linked nylon. The PSF and PES supports had similar performance at room temperature, but increasing temperature caused the supported membranes to fail. The ionic liquid with the PES support greatly affected the glass transition temperature, while with the PSF, the glass transition temperature was only slightly depressed. The cross-linked nylon support maintained performance without degradation over the temperature range 37-300°C with respect to its permeability and selectivity. However, while the cross-linked nylon support was able to withstand temperatures, the permeability continued to increase and the selectivity decreased with increasing temperature. Our studies indicated that further testing should examine the use of other ionic liquids, including those that form chemical complexes with CO2 based on

The killing of animals is the subject of societal and political debate. Wild geese are caught and killed on a regular basis for fauna conservation and damage control. Killing geese with carbondioxide (CO2) is commonly practiced, but not listed in legislation on the protection of flora and fauna,

Disclosed herein are combustion systems and power plants that incorporate sweep-based membrane separation units to remove carbondioxide from combustion gases. In its most basic embodiment, the invention is a combustion system that includes three discrete units: a combustion unit, a carbondioxide capture unit, and a sweep-based membrane separation unit. In a preferred embodiment, the invention is a power plant including a combustion unit, a power generation system, a carbondioxide capture unit, and a sweep-based membrane separation unit. In both of these embodiments, the carbondioxide capture unit and the sweep-based membrane separation unit are configured to be operated in parallel, by which we mean that each unit is adapted to receive exhaust gases from the combustion unit without such gases first passing through the other unit.

Extrusion process is one of the most important innovations of the 20th century applied in many industries. Extrusion is a technology that is increasingly used for the production of various food products, especially snacks and breakfast cereals. Supercritical carbondioxide (CO2) as a non-toxic, non-flammable and inexpensive, is applied in many processes, including the extrusion technology. Supercritical CO2 extrusion process (SCFX) found its application primarily in the processing and manufac...

The Department of Energy is the lead federal agency for research related to atmospheric carbondioxide. Its responsibility is to sponsor a program of relevant research, and to coordinate this research with that of others. As part of its responsibilities, the Department of Energy has prepared a research plan. The plan documented in this Summary delineated the logic, objectives, organization, background and current status of the research activities. The Summary Plan is based on research subplans in four specific areas: global carbon cycle, climate effects, vegetative response and indirect effects. These subplans have emanated from a series of national and international workshops, conferences, and from technical reports. The plans have been peer reviewed by experts in the relevant scientific fields. Their execution is being coordinated between the responsible federal and international government agencies and the involved scientific community.

Highlights: • The biologic methanation of exclusively gases like hydrogen and carbondioxide is feasible. • Electrical energy can be stored in the established gas grid by conversion to methane. • The quality of produced biogas is very high (c CH4 = 98 vol%). • The conversion rate is depending on H 2 -flow rate. - Abstract: A new method for the methanation of hydrogen and carbondioxide is presented. In a novel anaerobic trickle-bed reactor, biochemical catalyzed methanation at mesophilic temperatures and ambient pressure can be realized. The conversion of gaseous substrates by immobilized hydrogenotrophic methanogens is a unique feature of this reactor type. The already patented reactor produces biogas which has a very high quality (c CH4 = 97.9 vol%). Therefore, the storage of biogas in the existing natural gas grid is possible without extensive purification. The specific methane production was measured with P = 1.17 Nm CH4 3 /(m R 3 d). It is conceivable to realize the process at sites that generate solar or wind energy and sites subject to the conditions for hydrogen electrolysis (or other methods of hydrogen production). The combination with conventional biogas plants under hydrogen addition to methane enrichment is possible as well. The process enables the coupling of various renewable energy sources

A power generating plant using carbondioxide instead of water has been studied by the authors, as high efficiency can be obtained in high temperature range (higher than 650 deg C) and turbines become compact as compared with the Rankine steam cycle. In this paper, the theoretical analysis of the dynamic characteristics of this small power generating plant of supercritical pressure and the comparison with the experimental results are reported. In the theoretical analysis, the linear approximation method using small variation method was adopted for solution. Every component was modeled as the concentrated constant system, and the transfer function for each component was determined, then simulation was carried out for the total system synthesizing these components. The approximation of physical values, and the analysis of a plunger pump, a regenerator, a heater, a vapor valve, a turbine and a blower, piping, and pressure drop are described. The response to the stepwise changes of heating, flow rate, opening of a vapor valve and a load control valve for a blower was investigated. The theoretical anaysis and the experimental results were in good agreement, and this analysis is applicable to the carbondioxide plant of practical scale. (Kako, I.)

This note discusses the consequences for the sea transport sector between Norway and continental Europe of levying a carbondioxide tax on international bunker. The influence of such a tax on the operational costs of various types of ship and various transport routes is calculated. The profit obtainable from the following ways of adapting to an increased tax level is assessed: (1) Reducing the speed, (2) Rebuilding the engine to decrease fuel consumption, (3) Changing the design speed for new ships. It is found that a carbondioxide tax of NOK 200 per tonne of CO 2 will increase the transport costs by 3 - 15 percent. In the long run much of this may be transferred to the freight rates since so much of the sea transport are in segments in which the demand for the service is not sensitive to the prices. Even if the freight rates are not changed, a tax this size will not make it necessary to reduce the speed of the existing fleet. The income lost by taking fewer trips will exceed the costs saved in reducing the speed. However, the optimum design speed for new ships may be somewhat reduced (0.5 knots). Rebuilding engines to reduce the fuel consumption would pay off were it not for the fact that the remaining life of the present fleet is probably too short for this to be interesting

Supercritical fluid extraction is a novel diffusion and separation technique which exploits simultaneously the increase of vapor pressure and the difference of chemical affinities of fluids near the critical point. A solvent which is used as the supercritical fluid has the following features: the critical point exists in the position of relatively ease of handling, the solvent is applicable to the extraction of a physiological active substance of thermal instability. Carbondioxide as the solvent is non-flammable, non-corrosive, non-toxic, cheap, and readily available of high purity. The results of studies on the use of supercritical carbondioxide (SC-CO{sub 2}) as a solvent for natural products in the fermentation and food industries, were collected. SC-CO{sub 2} extraction are used in many fields, examples for the application are as follows: removal of organic solvents from antibiotics; extraction of vegetable oils contained in wheat germ oil, high quality mustard seeds, rice bran and so on; brewing of sake using rice and rice-koji; use as a non-aqueous medium for the synthesis of precursors of the Aspartame; and use in sterilization. 66 refs., 17 figs., 21 tabs.

Carbondioxide is the main greenhouse gas and its major source is combustion of fossil fuels for power generation. The objective of this study is to carry out the steady-state sensitivity analysis for chemical absorption of carbondioxide capture from flue gas using monoethanolamine solvent. First...... equilibrium and associated property models are used. Simulations are performed to investigate the sensitivity of the process variables to change in the design variables including process inputs and disturbances in the property model parameters. Results of the sensitivity analysis on the steady state...... performance of the process to the L/G ratio to the absorber, CO2 lean solvent loadings, and striper pressure are presented in this paper. Based on the sensitivity analysis process optimization problems have been defined and solved and, a preliminary control structure selection has been made....

grass) and Osteospermun sinuatum (Karoo-bush) plants during the flag leaf and flower bud stages respectively resulted in a sharp decline in net carbondioxide absorption. As new photosynthetic material was produced the total carbon ...

National Aeronautics and Space Administration — Isotopic analysis of carbondioxide is an important tool for characterization of the exchange and transformation of carbon between the biosphere and the atmosphere....

Supported liquid membranes are a class of materials that allow the researcher to utilize the wealth of knowledge available on liquid properties as a direct guide in the development of a capture technology. These membranes also have the advantage of liquid phase diffusivities higher than those observed in polymeric membranes which grant proportionally greater permeabilities. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high carbondioxide solubility relative to light gases such as hydrogen, are an excellent candidate for this type of membrane since they have negligible vapor pressure and are not susceptible to evaporation. A study has been conducted evaluating the use of several ionic liquids, including 1-hexyl-3-methyl-imidazolium bis(trifuoromethylsulfonyl)imide, 1-butyl-3-methyl-imidazolium nitrate, and 1-ethyl-3-methyl-imidazolium sulfate in supported ionic liquid membranes for the capture of carbondioxide from streams containing hydrogen. In a joint project, researchers at the University of Notre Dame lent expertise in ionic liquid synthesis and characterization, and researchers at the National Energy Technology Laboratory incorporated candidate ionic liquids into supports and evaluated the resulting materials for membrane performance. Initial results have been very promising with carbondioxide permeabilities as high as 950 barrers and significant improvements in carbondioxide/hydrogen selectivity over conventional polymers at 37C and at elevated temperatures. Results include a comparison of the performance of several ionic liquids and a number of supports as well as a discussion of innovative fabrication techniques currently under development.

A pure carbondioxide torch is generated by making use of 2.45 GHz microwave. Carbondioxide gas becomes the working gas and produces a stable carbondioxide torch. The torch volume is almost linearly proportional to the microwave power. Temperature of the torch flame is measured by making use of optical spectroscopy and thermocouple. Two distinctive regions are exhibited, a bright, whitish region of high-temperature zone and a bluish, dimmer region of relatively low-temperature zone. Study of carbondioxide disintegration and gas temperature effects on the molecular fraction characteristics in the carbondioxide plasma of a microwave plasma torch under atmospheric pressure is carried out. An analytical investigation of carbondioxide disintegration indicates that substantial fraction of carbondioxide molecules disintegrate and form other compounds in the torch. For example, the normalized particle densities at center of plasma are given by nCO2/nN = 6.12 × 10-3, nCO/nN = 0.13, nC/nN = 0.24, nO/nN = 0.61, nC2/nN = 8.32 × 10-7, nO2/nN = 5.39 × 10-5, where nCO2, nCO, nC, nO, nC2, and nO2 are carbondioxide, carbon monoxide, carbon and oxygen atom, carbon and oxygen molecule densities, respectively. nN is the neutral particle density. Emission profiles of the oxygen and carbon atom radicals and the carbon monoxide molecules confirm the theoretical predictions of carbondioxide disintegration in the torch.

A pure carbondioxide torch is generated by making use of 2.45 GHz microwave. Carbondioxide gas becomes the working gas and produces a stable carbondioxide torch. The torch volume is almost linearly proportional to the microwave power. Temperature of the torch flame is measured by making use of optical spectroscopy and thermocouple. Two distinctive regions are exhibited, a bright, whitish region of high-temperature zone and a bluish, dimmer region of relatively low-temperature zone. Study of carbondioxide disintegration and gas temperature effects on the molecular fraction characteristics in the carbondioxide plasma of a microwave plasma torch under atmospheric pressure is carried out. An analytical investigation of carbondioxide disintegration indicates that substantial fraction of carbondioxide molecules disintegrate and form other compounds in the torch. For example, the normalized particle densities at center of plasma are given by nCO2/nN = 6.12 × 10(-3), nCO/nN = 0.13, nC/nN = 0.24, nO/nN = 0.61, nC2/nN = 8.32 × 10(-7), nO2/nN = 5.39 × 10(-5), where nCO2, nCO, nC, nO, nC2, and nO2 are carbondioxide, carbon monoxide, carbon and oxygen atom, carbon and oxygen molecule densities, respectively. nN is the neutral particle density. Emission profiles of the oxygen and carbon atom radicals and the carbon monoxide molecules confirm the theoretical predictions of carbondioxide disintegration in the torch.

A pure carbondioxide torch is generated by making use of 2.45 GHz microwave. Carbondioxide gas becomes the working gas and produces a stable carbondioxide torch. The torch volume is almost linearly proportional to the microwave power. Temperature of the torch flame is measured by making use of optical spectroscopy and thermocouple. Two distinctive regions are exhibited, a bright, whitish region of high-temperature zone and a bluish, dimmer region of relatively low-temperature zone. Study of carbondioxide disintegration and gas temperature effects on the molecular fraction characteristics in the carbondioxide plasma of a microwave plasma torch under atmospheric pressure is carried out. An analytical investigation of carbondioxide disintegration indicates that substantial fraction of carbondioxide molecules disintegrate and form other compounds in the torch. For example, the normalized particle densities at center of plasma are given by nCO2/nN = 6.12 × 10−3, nCO/nN = 0.13, nC/nN = 0.24, nO/nN = 0.61, nC2/nN = 8.32 × 10−7, nO2/nN = 5.39 × 10−5, where nCO2, nCO, nC, nO, nC2, and nO2 are carbondioxide, carbon monoxide, carbon and oxygen atom, carbon and oxygen molecule densities, respectively. nN is the neutral particle density. Emission profiles of the oxygen and carbon atom radicals and the carbon monoxide molecules confirm the theoretical predictions of carbondioxide disintegration in the torch. PMID:26674957

Intensive research has been undertaken on carbondioxide efflux from lakes, estuaries and oceans, but much less attention has been given to rivers and streams, especially lower order streams. River systems are often over-saturated with carbondioxide and so tend to act as sources of carbondioxide to the atmosphere. It has been thought that rivers act as pipes carrying this terrestrial carbon to the oceans. However, recent studies have shown that a significant amount of the carbon is reprocessed within the system in a series of transformations and losses. Fluvial evasion of carbondioxide is now recognised to be a significant component of carbon cycles, however the factors controlling carbondioxide efflux and its magnitude remain poorly understood and quantified. This research aims to quantify, and better understand the controls on, freshwater carbondioxide evasion. Data are presented here from field measurements that commenced in Sept 2013 in two contrasting Scottish rivers: the River Kelvin which has a large (335 km.sq) part-urban catchment with predominantly non-peat soils and Drumtee Water, a small (9.6 km.sq) rural catchment of peat soils and agricultural land. Using a floating chamber with the headspace connected to an infrared gas analyser to measure changes in carbondioxide concentration, efflux rates from 0.22 - 47.4 μmol CO2/m.sq/sec were measured, these close to the middle of the range of previously reported values. At one site on the River Kelvin in May 2013 an influx of -0.61 - -3.53 μmol CO2/m.sq/sec was recorded. Whereas previous research finds carbondioxide efflux to increase with decreasing river size and a more organic-rich soil catchment, here the controls on carbondioxide evasion are similar across the contrasting catchments. Carbondioxide evasion shows seasonality, with maximum fluxes in the summer months being up to twice as high as the winter maxima. Linear regression demonstrates that evasion increases with increased flow velocity

We develop a numerical simulation of the global biogeochemical cycles of carbon that works over time scales extending from years to millions of years. The ocean is represented by warm and cold shallow water reservoirs, a thermocline reservoir, and deep Atlantic, Indian, and Pacific reservoirs. The atmosphere is characterized by a single carbon reservoir and the global biota by a single biomass reservoir. The simulation includes the rock cycle, distinguishing between shelf carbonate and pelagic carbonate precipitation, with distinct lysocline depths in the three deep ocean reservoirs. Dissolution of pelagic carbonates in response to decrease in lysocline depth is included. The simulation is tuned to reproduce the observed radiocarbon record resulting from atomic weapon testing. It is tuned also to reproduce the distribution of dissolved phosphate and total dissolved carbon between the ocean reservoirs as well as the carbon isotope ratios for both 13C and 14C in ocean and atmosphere. The simulation reproduces reasonably well the historical record of carbondioxide partial pressure as well as the atmospheric isotope ratios for 13C and 14C over the last 200 yr as these have changed in response to fossil fuel burning and land use changes, principally forest clearance. The agreements between observation and calculation involves the assumption of a carbondioxide fertilization effect in which the rate of production of biomass increases with increasing carbondioxide partial pressure. At present the fertilization effect of increased carbondioxide outweighs the effects of forest clearance, so the biota comprises an overall sink of atmospheric carbondioxide sufficiently large to bring the budget approximately into balance. This simulation is used to examine the future evolution of carbondioxide and its sensitivity to assumptions about the rate of fossil fuel burning and of forest clearance. Over times extending up to thousands of years, the results are insensitive to the

Full Text Available The existing understanding of interglacial periods is that they are initiated by Milankovitch cycles enhanced by rising atmospheric carbondioxide concentrations. During interglacials, global temperature is also believed to be primarily controlled by carbondioxide concentrations, modulated by internal processes such as the Pacific Decadal Oscillation and the North Atlantic Oscillation. Recent work challenges the fundamental basis of these conceptions.

The existing understanding of interglacial periods is that they are initiated by Milankovitch cycles enhanced by rising atmospheric carbondioxide concentrations. During interglacials, global temperature is also believed to be primarily controlled by carbondioxide concentrations, modulated by internal processes such as the Pacific Decadal Oscillation and the North Atlantic Oscillation. Recent work challenges the fundamental basis of these conceptions.

Wheat germ oil was extracted using an environmental friendly solvent, supercritical carbondioxide (SCCO2) at a semi-batch flow extraction process. The supercritical carbondioxide (SC-CO2) extraction was carried out to extract oil at temperature of 40°C and pressure of 25 MPa. Ethanolysis was performed with 1 ...

The biological means of CO2 fixation using various microorganisms is gaining importance because database of their substantial role in reversing global warming. Carbondioxide utilizing strain database (CSD) presents a comprehensive overview of microorganisms involved in biological fixation of carbondioxide. As a part ...

Global warming is a current environmental issue that has been linked to an increase in anthropogenic carbondioxide in the atmosphere. To raise awareness of the problem, various simple experiments have been proposed to demonstrate the effect of carbondioxide on the planet's temperature. This article describes a similar experiment, which…

Carbondioxide at high pressure can retard microbial growth and sometimes kill microorganisms depending on values of applied pressure, temperature and exposure time. In this study the effect of high pressurised carbondioxide (HPCD) on Escherichia coli was investigated. Culture of E. coli was subjected to high ...

This article deals with carbondioxide production from farm animals; more specifically, it addresses the possibilities of using the measured carbondioxide concentration in animal houses as basis for estimation of ventilation flow (as the ventilation flow is a key parameter of aerial emissions from

A photocatalytic system for converting carbondioxide into carbon monoxide was designed and constructed. The system relies on thin films of the photocatalyst prepared at low temperature using spray coating. We formulated inks based on the well-known photocatalyst titanium dioxide and characterized...

A new and general type of process for the chemical industry is presented using ionic liquids and supercritical carbondioxide as combined reaction and separation media. In this process, the carbondioxide pressure controls the miscibility of reactants, products, catalyst and ionic liquid, enabling

In the present work the absorption of carbondioxide into aqueous piperazine (PZ) solutions has been studied in a stirred cell, at low to moderate temperatures, piperazine concentrations ranging from 0.6 to 1.5 kmol m- 3, and carbondioxide pressures up to 500 mbar, respectively. The obtained

This paper examines the synergistic action of carbondioxide and nisin on Listeria monocytogenes Scott A wild-type and nisin-resistant (Nis(r)) cells grown in broth at 4 degrees C. Carbondioxide extended the lag phase and decreased the specific growth rate of both strains, but to a greater degree...

In accordance with one aspect, the present invention provides an amino-siloxane composition comprising at least one of structures I, II, III, IV or V said compositions being useful for the capture of carbondioxide from gas streams such as power plant flue gases. In addition, the present invention provides methods of preparing the amino-siloxane compositions are provided. Also provided are methods for reducing the amount of carbondioxide in a process stream employing the amino-siloxane compositions of the invention as species which react with carbondioxide to form an adduct with carbondioxide. The reaction of the amino-siloxane compositions provided by the present invention with carbondioxide is reversible and thus, the method provides for multicycle use of said compositions.

Full Text Available This study aims to determine the effects of the automotive industry on carbondioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbondioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbondioxide emissions in France, Sweden, Spain, Hungary and Japan. In addition, significant relations were observed between output and carbondioxide discharges in Spain, Canada, India and Japan. Changes in output had substantial impact on emissions in Germany, Canada and India. The results also show that the number of passenger cars influences the magnitude of emissions in multiple economies. In conclusion, the automotive industry has to be considered in policies that aim to reduce carbondioxide emissions.

Carbondioxide has long been the nemesis of environmentalists because of its role in global warming, but under just the right conditions-namely, high pressure and high temperature its one of nature's best and most environmentally benign solvents. Decaf-coffee lovers, for instance, benefit from its ability to remove caffeine from coffee beans.During the last few years, carbondioxide has also made inroads in the dry-cleaning industry, providing a safe cleaning alternative to the chemical perchloroethylene. But it's on the high-tech front that carbondioxide may make its biggest impact. T here are huge opportunities. Scientists have known for more than a century that at 75 times atmospheric pressure and 31 degree centigrade, carbondioxide goes into and odd state that chemists called s upercritical . What's interesting to industry is that supercritical carbondioxide may be an enabling technology for going to smaller dimensions.(Author)

. The Menzengraben mine experienced an extreme outburst in 1953, possibly involving a several thousand tons of carbondioxide. This source of accidents fills an important gap in the available carbondioxide accident history and may provide a unique empirical perspective on the hazards of handling very large amounts...

We demonstrate that the key step for the reaction of CO 2 with hydrogen on Ni(110) is a change of the activated molecule coordination to the metal surface. At 90 K, CO 2 is negatively charged and chemically bonded via the carbon atom. When the temperature is increased and H approaches, the H-CO 2 complex flips and binds to the surface through the two oxygen atoms, while H binds to the carbon atom, thus yielding formate. We provide the atomic-level description of this process by means of conventional ultrahigh vacuum surface science techniques combined with density functional theory calculations and corroborated by high pressure reactivity tests. Knowledge about the details of the mechanisms involved in this reaction can yield a deeper comprehension of heterogeneous catalytic organic synthesis processes involving carbondioxide as a reactant. We show why on Ni the CO 2 hydrogenation barrier is remarkably smaller than that on the common Cu metal-based catalyst. Our results provide a possible interpretation of the observed high catalytic activity of NiCu alloys.

Carbondioxide (CO2) transfer from inland waters to the atmosphere, known as CO2 evasion, is a component of the global carbon cycle. Global estimates of CO2 evasion have been hampered, however, by the lack of a framework for estimating the inland water surface area and gas transfer velocity and by the absence of a global CO2 database. Here we report regional variations in global inland water surface area, dissolved CO2 and gas transfer velocity. We obtain global CO2 evasion rates of 1.8 petagrams of carbon (Pg C) per year from streams and rivers and 0.32 Pg C yr−1 from lakes and reservoirs, where the upper and lower limits are respectively the 5th and 95th confidence interval percentiles. The resulting global evasion rate of 2.1 Pg C yr−1 is higher than previous estimates owing to a larger stream and river evasion rate. Our analysis predicts global hotspots in stream and river evasion, with about 70 per cent of the flux occurring over just 20 per cent of the land surface. The source of inland water CO2 is still not known with certainty and new studies are needed to research the mechanisms controlling CO2 evasion globally.

A solid sorbent for the capture and the transport of carbondioxide gas is provided having at least one first layer of a positively charged material that is polyethylenimine or poly(allylamine hydrochloride), that captures at least a portion of the gas, and at least one second layer of a negatively charged material that is polystyrenesulfonate or poly(acryclic acid), that transports the gas, wherein the second layer of material is in juxtaposition to, attached to, or crosslinked with the first layer for forming at least one bilayer, and a solid substrate support having a porous surface, wherein one or more of the bilayers is/are deposited on the surface of and/or within the solid substrate. A method of preparing and using the solid sorbent is provided.

The large prevalence of respiratory acid-base disorders overlapping metabolic acidosis in hemodialysis population should prompt nephrologists to deal with the partial pressure of carbondioxide (pCO2) complying with the reduced bicarbonate concentration. What the most suitable formula to compute pCO2 is reviewed. Then, the neglected issue of CO2 content in the dialysis fluid is under the spotlight. In fact, a considerable amount of CO2 comes to patients' bloodstream every hemodialysis treatment and "acidosis by dialysate" may occur if lungs do not properly clear away this burden of CO2. Moreover, vascular access recirculation may be easy diagnosed by detecting CO2 in the arterial line of extracorporeal circuit if CO2-enriched blood from the filter reenters arterial needle.

Conventional heterogeneous dispersion polymerizations of unsaturated monomers are performed in either aqueous or organic dispersing media with the addition of interfacially active agents to stabilize the colloidal dispersion that forms. Successful stabilization of the polymer colloid during polymerization results in the formation of high molar mass polymers with high rates of polymerization. An environmentally responsible alternative to aqueous and organic dispersing media for heterogeneous dispersion polymerizations is described in which supercritical carbondioxide (CO_2) is used in conjunction with molecularly engineered free radical initiators and amphipathic molecules that are specifically designed to be interfacially active in CO_2. Conventional lipophilic monomers, exemplified by methyl methacrylate, can be quantitatively (>90 percent) polymerized heterogeneously to very high degrees of polymerization (>3000) in supercritical CO_2 in the presence of an added stabilizer to form kinetically stable dispersions that result in micrometer-sized particles with a narrow size distribution.

; however, differences may occur in response to soil spatial variability. A better coverage of spatial variability is more easily addressed using manually operated systems whereas temporal variability can be covered using the automated system. Depending on the aim of the study, the two systems may be used......Carbondioxide (CO2) concentrations in arable soil profiles are influenced by autotrophic and heterotrophic respiration as well as soil physical properties that regulate gas transport. Whereas different methods have been used to assess dynamics of soil CO2 concentrations, our understanding...... on the comparability of results obtained using different methods is limited. We therefore aimed to compare the dynamics in soil CO2 concentrations obtained from an automated system (GMP343 sensors) to those from a manually operated measurement system (i.e., soil gas sampled using stainless steel needles and rods...

The purpose is to attempt a general introduction to pulsed carbondioxide lasers of the kind used or proposed for laser radar applications. Laser physics is an excellent example of a cross-disciplinary topic, and the molecular spectroscopy, energy transfer, and plasma kinetics of the devices are explored. The concept of stimulated emission and population inversions is introduced, leading on to the molecular spectroscopy of the CO2 molecule. This is followed by a consideration of electron-impact pumping, and the pertinent energy transfer and relaxation processes which go on. Since the devices are plasma pumped, it is necessary to introduce a complex subject, but this is restricted to appropriate physics of glow discharges. Examples of representative devices are shown. The implications of the foregoing to plasma chemistry and gas life are discussed.

This petition requests EPA to promulgate regulations under section 6 of TSCA to protect “public health and the environment from the serious harms associated with anthropogenic emissions of carbondioxide, including ocean acidification.

In this paper, laminar convection flows induced by carbondioxide absorption are addressed from experimental, numerical and theoretical points of view. A vertical glass tube (of centimetre scale) filled with distilled water is subjected to a sudden increase in the partial pressure of carbondioxide. As a result of the diffusion of the gas into the unsaturated solution, a thin layer of fluid located underneath the surface becomes heavier. This initial density gradient first destabilizes to form a plume, which goes downwards through the entire cell. After a first transient pulsating regime (periodic succession of such Rayleigh-Benard plumes), a stationary flow settles in the tube, which is maintained by the constant supply of gas at the surface. At late stages, this stationary regime is followed by an aperiodic regime, which lasts until the complete saturation of the solution (thermodynamic equilibrium). The present study only focuses on the stationary regime, whose characteristics appear to be almost independent of the Bond number and the aspect ratio but strongly dependent on the chemical Rayleigh number. Three decades of Rayleigh numbers are explored using particle image velocimetry measurements, which allows for a precise determination of the scaling exponents for the vertical velocity amplitude and the plume width. The assumption that gravity and a constant pressure gradient balance the viscous effects enables us to derive an analytic expression for the stationary vertical velocity on the axis, which scales as Ra 2/3 (ln Ra) 1/3 . As a consequence, the width of the plume scales as Ra -1/6 (ln Ra) -1/3 and the mass Nusselt number as (Ra= ln Ra) 1/3 . These scalings are in excellent agreement with the experimental and numerical results. The multiplicative constants of these scalings can also be calculated and show a fairly good agreement if a rigid boundary condition (no-slip) is assumed at the free surface. (authors)

A method for increasing the efficiency of drilling operations by using a drilling fluid material that exists as supercritical fluid or a dense gas at temperature and pressure conditions existing at a drill site. The material can be used to reduce mechanical drilling forces, to remove cuttings, or to jet erode a substrate. In one embodiment, carbondioxide (CO.sub.2) is used as the material for drilling within wells in the earth, where the normal temperature and pressure conditions cause CO.sub.2 to exist as a supercritical fluid. Supercritical carbondioxide (SC--CO.sub.2) is preferably used with coiled tube (CT) drilling equipment. The very low viscosity SC--CO.sub.2 provides efficient cooling of the drill head, and efficient cuttings removal. Further, the diffusivity of SC--CO.sub.2 within the pores of petroleum formations is significantly higher than that of water, making jet erosion using SC--CO.sub.2 much more effective than water jet erosion. SC--CO.sub.2 jets can be used to assist mechanical drilling, for erosion drilling, or for scale removal. A choke manifold at the well head or mud cap drilling equipment can be used to control the pressure within the borehole, to ensure that the temperature and pressure conditions necessary for CO.sub.2 to exist as either a supercritical fluid or a dense gas occur at the drill site. Spent CO.sub.2 can be vented to the atmosphere, collected for reuse, or directed into the formation to aid in the recovery of petroleum.

Full Text Available This paper calculates the carbondioxide mitigation benefit of high-speed railway based on the carbondioxide tax policy. We define the carbondioxide emission system boundary for high-speed railway in its whole life cycle and estimate the life cycle carbondioxide inventories during its construction, application, and recovery stages. And then we establish a theoretical model to calculate the life cycle carbondioxide mitigation quantity for high-speed railway when compared with road transport and then calculate its carbondioxide mitigation benefit. The numerical example shows that the carbondioxide mitigation benefit of high-speed railway is better than that of road transport from the whole life cycle perspective.

River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle(1). A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbondioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial

The performance of isotope separation of carbon-13 by chemical exchange between carbondioxide and carbamic acid was studied. The working fluid used in the study was a solution of DNBA, (C 4 H 9 ) 2 NH and n-octane mixture. Factors related to the isotope exchange rate were measured, such as the absorption rate of carbondioxide into the solution of DNBA and n-octane, the isotope exchange rate and the separation factor in the reaction between CO 2 and carbamic acid. The absorption of CO 2 into the working fluid was the sum of chemical absorption by DNBA and physical absorption by n-octane. The absorption of carbondioxide into the working fluid was negligible at temperatures over 90 0 C, but increased gradually at lower temperatures. Carbondioxide was absorbed into DNBA by chemical absorption, and DNBA was converted to carbamic acid by the reaction. The reaction for synthesis and decomposition of carbamic acid was reversible. The separation factor in equilibrium reached a large value at lower temperatures. The isotope exchange rate between gas and liquid was proportional to the product of the concentration of carbamic acid and the concentration of CO 2 by physical absorption. The isotope separation of carbon by chemical exchange reaction is better operated under the conditions of lower temperature and higher pressure. (author)

Full Text Available Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2. In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbondioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbondioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbondioxide concentration could affect nodulation efficiency.

Highlights: • A model of open refrigeration system is developed. • The state of CO 2 has great effect on Refrigeration capacity loss by heat transfer. • Refrigeration capacity loss by remaining CO 2 has little relation to the state of CO 2 . • Calculation results are in agreement with the test results. - Abstract: Based on the analysis of the properties of carbondioxide, an open carbondioxide refrigeration system is proposed, which is responsible for the situation without external electricity unit. A model of open refrigeration system is developed, and the relationship between the storage environment of carbondioxide and refrigeration capacity is conducted. Meanwhile, a test platform is developed to simulation the performance of the open carbondioxide refrigeration system. By comparing the theoretical calculations and the experimental results, several conclusions are obtained as follows: refrigeration capacity loss by heat transfer in supercritical state is much more than that in two-phase region and the refrigeration capacity loss by remaining carbondioxide has little relation to the state of carbondioxide. The results will be helpful to the use of open carbondioxide refrigeration

The present invention provides a resin-wafer electrodeionization (RW-EDI) apparatus including cathode and anode electrodes separated by a plurality of porous solid ion exchange resin wafers, which when in use are filled with an aqueous fluid. The apparatus includes one or more wafers comprising a basic ion exchange medium, and preferably includes one or more wafers comprising an acidic ion exchange medium. The wafers are separated from one another by ion exchange membranes. The fluid within the acidic and/or basic ion exchange wafers preferably includes, or is in contact with, a carbonic anhydrase (CA) enzyme to facilitate conversion of bicarbonate ion to carbondioxide within the acidic medium. A pH suitable for exchange of CO.sub.2 is electrochemically maintained within the basic and acidic ion exchange wafers by applying an electric potential across the cathode and anode.

Links proposed low-energy scenarios for different Western European countries with the amount of pollutants that may result from these scenarios. Sulfur dioxide, nitrogen oxide, and carbondioxide emissions are calculated for the 10 countries for which low-energy scenarios are available, resulting in reductions of 54%, 37%, and 40%, respectively.…

Animal digestion is responsible for the production of both carbondioxide and methane, while breathing produces only carbondioxide. The author described the digestion mechanism of ruminants, explaining that they produce higher levels of methane and carbondioxide than other animals. Fermentation stoichiometry of ruminants was also discussed along with the influence that diet has on methane production. It was noted that methane production can be decreased by increasing animal productivity, or by using ionophore antibiotics and long chain fatty acids. Test results from each of these methods have revealed side effects and none appears to be applicable for the time being. 10 refs., 1 tab., 1 fig

An in-house set-up was developed for determining the permeability of paint films towards carbondioxide. The system implemented the so-called Wicke-Kallenback method, described in EN 1062-6. This method consists of a two-chamber permeation cell divided by a supported paint film. A carbondioxide/nitrogen mixture stream (15% CO2/85% N-2) is fed to the retentate chamber and a nitrogen carrier stream is fed to the permeate chamber. Carbondioxide permeates from the retentate to the permeate cham...

At present, the literature lacks a geologic-based assessment methodology for numerically estimating injectivity, lateral migration, and subsequent long-term containment of supercritical carbondioxide that has undergone geologic sequestration into subsurface formations. This study provides a method for and quantification of first-order approximations for the time scale of supercritical carbondioxide lateral migration over a one-kilometer distance through a representative volume of rock. These calculations provide a quantified foundation for estimating injectivity and geologic storage of carbondioxide.

The supercritical carbondioxide flow has been visualized under forced convection by a Mach-Zehnder interferometry system. The forced convection heat transfer has been examined by an one-sided wall heater in the vertical rectangular test section. Temperature and density distributions of the heated carbondioxide inside the test section have been calculated from the measured interferometry projections for the visible interferograms conditions. The relationship of the temperature distributions with the physical conditions has been analyzed to inspect the forced convection heat transfer of the supercritical carbondioxide flow. (author)

The methods of gravitmetric and X-ray phase analysis as well as analysis of composition of gases in the heating chamber have been used to investigate the mechanism of titanium and vanadium interaction with carbondioxide in the 300-1000 deg C temperature range. The analogy of mechanisms of the interaction of titanium and vanadium with carbondioxide in oxides production on the metal surface with subsequent carbidizing treatment at temperatures above 800 deg C is shown. Temperature limits of material operation on the base of titanium or vanadium in carbondioxide must not exceed 400 or 600 deg C, respectively

Carbondioxide capture and storage (CCS) presents one potential technological solution for mitigating the atmospheric emission of carbondioxide sources. However, CCS is a relatively new technology with associated uncertainties and perceived risks. For this reason, a growing body of research now focuses on public perceptions and potential for societal acceptance of CCS technology. Almost all explanations of CCS technology make reference to carbondioxide, with an assumption that the general public understands CO2. It has become apparent that the general public’s knowledge and understanding of CO2’s properties influences how they engage with CO2 emitting industries and CCS technologies. However, surprisingly little research has investigated public perceptions, knowledge, and understanding of CO2. This investigation attempts to fill that gap. This report describes an investigation of how citizens of three countries (Japan, Australia, and the Netherlands) perceive CO2. Furthermore, it attempts to relate individual perceptions of CO2 to perceptions of CCS, and to determine how information provision about the underlying properties and characteristics of CO2 influences individual attitudes towards low carbon energy options, particularly CCS. In brief, the research had four ultimate aims. It aimed to: Explore the public’s knowledge and understanding of the properties of CO2; Examine the influence of that knowledge on their perceptions of CO2 and CCS; Investigate how information provision about the underlying properties and characteristics of CO2 influences individual attitudes towards CCS; and Identify if any differences between countries exist in relation to values and beliefs, knowledge of CO2’s properties, and CCS perceptions.

The atmospheric carbondioxide concentration plays a crucial role in the radiative balance and as such has a strong influence on the evolution of climate. Because of the numerous interactions between climate and the carbon cycle, it is necessary to include a model of the carbon cycle within a

Full Text Available The reactivity of carbondioxide with methanol to form dimethyl carbonate was studied in the presence of the n-butylmethoxytin compounds n-Bu3SnOCH3, n-Bu2Sn(OCH32 , and [n-Bu2(CH3OSn]2 O. The reaction occurred under solventless conditions at 423 K and was produced by an increase in CO2 pressure. This beneficial effect is primarily attributed to phase behavior. The mass transfer under liquid-vapor biphasic conditions was not limiting when the system reached the supercritical state for a CO2 pressure higher than 16 MPa. Under these conditions, CO2 acted as a reactant and a solvent.

A novel method and system of separating carbondioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbondioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbondioxide gas, permitting carbondioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

A novel method and system of separating carbondioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbondioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbondioxide gas, permitting carbondioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

Air quality in urban areas is a cause of concern because of increased industrial activities that contribute to large quantities of emissions. The study assess levels and variations of carbon monoxide (CO), nitrogen dioxide (NO2) and sulfur dioxide (SO2) in Blantyre, Malawi using a stationary environmental monitoring station ...

National Aeronautics and Space Administration — An electrochemical reactor is proposed by MicroCell Technologies, LLC to electrochemically reduce carbondioxide to oxygen. In support of NASA's advanced life...

National Aeronautics and Space Administration — Carbondioxide (CO2) is an important greenhouse gas released through natural processes such as respiration and volcano eruptions and through huma activities such as...

significantly with depth Bicarbonate ion is quantitatively the major component of the carbondioxide system The observed vertical distributions are discussed in terms of biological and geochemical processes in the sea...

National Aeronautics and Space Administration — Phase 1 has seen the development of a revolutionary new type of sensor for making carbondioxide (CO2) measurements from small Unmanned Aircraft Systems (UAS) and...

National Aeronautics and Space Administration — Opus 12 has redesigned the cathode of the commercially available PEM water electrolyzer such that it can support the reduction of carbondioxide into ethylene and...

The understanding of biogeochemical cycling of carbondioxide and nitrous oxide in the oceans is essential for predicting the fate of anthropogenically emitted components. The North Indian Ocean, with its diverse regimes, provides us with a natural...

National Aeronautics and Space Administration — Mesa Photonics proposes development of a passive optical sensor for simultaneous high-precision measurement of oxygen and carbondioxide profiles within the full...

National Aeronautics and Space Administration — An electrochemical reactor is proposed by MicroCell Technologies, LLC to electrochemically reduce carbondioxide to oxygen. In support of NASA's advanced life...

To report the use of pumpless extracorporeal carbondioxide removal in two cases of acute severe asthma. Case reports. Adult general intensive care unit, Leeds General Infirmary, Leeds, UK. A 74-yr-old male and 52-yr-old female with life-threatening asthma developed progressive hypercapnia and severe acidosis that proved nonresponsive to all other therapies. Initiation of extracorporeal arteriovenous carbondioxide removal using the Novalung device (Novalung GmbH, Lotzenäcker 3, D-72379 Hechingen, Germany). The addition of extracorporeal carbondioxide removal to mechanical ventilation corrected hypercapnia and acidosis, allowing reduction of other supportive measures. In both cases, adequate gas exchange was maintained until their underlying condition improved sufficiently for device removal. The two patients were subsequently weaned from mechanical ventilation and made a full recovery. Extracorporeal carbondioxide removal proved to be a valuable adjunct to mechanical ventilation and other medical treatment.

Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbondioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

Exposure to carbondioxide (CO2) is the most prevalent method used to euthanize rodents in biomedical research. The purpose of this study was to determine the time of CO2 exposure required to euthanize neonatal mice (0 to 10 days old). Multiple groups of mice were exposed to 100% CO 2 for time periods between 5 and 60 min. Mice were placed in room air for 10 or 20 min after CO2 exposure, to allow for the chance of recovery. If mice recovered at one time point, a longer exposure was examined. Inbred and outbred mice were compared. Results of the study indicated that time to death varied with the age of the animals and could be as long as 50 min on the day of birth and differed between inbred and outbred mice. Institutions euthanizing neonatal mice with CO2 may wish to adjust their CO 2 exposure time periods according the age of the mice and their genetic background. Copyright 2005 by the American Association for Laboratory Animal Science.

The main contribution of this work is the development of a simple and reliable modelling technique on carbondioxide removal describing the vapor-liquid equilibria of CO 2 in aqueous alkanolamine solutions. By making use of measured pH data, the author has circumvented the problem of estimating interaction parameters, activity coefficients, and equilibrium constants in the prediction of vapor-liquid equilibria. The applicability of the model is best demonstrated on the tertiary amine system using MDEA. For this system, the VLE is accurately represented for temperatures in the range 25 to 140 o C, for CO 2 loadings from 0.001 to 1 mol/mol, and for amine molarities usually encountered in acid gas treating processes. The absorption of CO 2 into solutions containing the sterically hindered amine AMP, is also well described by the model. The equilibrium of CO 2 in mixed solvents containing a glycol (TEG,DEG) and an alkonolamine (MEA,DEA) has been measured at temperatures encountered in the absorption units. An equilibrium model has been developed for the CO 2 /TEG/MEA system for estimation of CO 2 partial pressures, covering loadings and temperatures for both absorption and desorption conditions. An important spin-off of the work described is that two new experimental set-ups have been designed and built. 154 refs., 38 figs., 22 tabs

The objectives of this study are to predict quantitatively groundwater and carbondioxide flow in deep saline sandstone aquifers under various carbondioxide injection schemes (injection rate, injection period) and to analyze integratively impacts of such carbondioxide injection schemes on deep groundwater (brine) and carbondioxide leakage risk through abandoned wells or faults. In order to achieve the first objective, a series of process-level prediction modeling of groundwater and carbondioxide flow in a deep saline sandstone aquifer under several carbondioxide injection schemes was performed using a multiphase thermo-hydrological numerical model TOUGH2 (Pruess et al., 1999). The prediction modeling results show that the extent of carbondioxide plume is significantly affected by such carbondioxide injection schemes. In order to achieve the second objective, a series of system-level analysis modeling of deep groundwater and carbondioxide leakage risk through an abandoned well or a fault under several carbondioxide injection schemes was then performed using a brine and carbondioxide leakage risk analysis model CO2-LEAK (Kim, 2012). The analysis modeling results show that the rates and amounts of deep groundwater and carbondioxide leakage through an abandoned well or a fault increase as the carbondioxide injection rate increases. However, the rates and amounts of deep groundwater and carbondioxide leakage through an abandoned well or a fault decrease as the carbondioxide injection period increases. These system-level analysis modeling results for deep groundwater and carbondioxide leakage risk can be utilized as baseline data for establishing guidelines to mitigate anticipated environmental adverse effects on shallower groundwater systems (aquifers) when deep groundwater and carbondioxide leakage occur. This work was supported by the Geo-Advanced Innovative Action (GAIA) Program funded by the Korea Environmental Industry and Technology Institute

Detection of expired carbondioxide is one of the most reliable methods of avoiding accidental esophageal intubation. Although capnography has become a standard monitoring technique in the hospital operating room, it is rarely available in the office setting or other arenas where emergency endotracheal intubation may be required. A new and inexpensive device, however, has been developed for assessing end-tidal carbondioxide. This semi-quantitative detector fits between the endotracheal tube ...

Capture and sequestration of carbondioxide is one of the most critical challenges today for businesses and governments worldwide. Thousands of emitting power plants and industries worldwide face this costly challenge – reduce the CO2 emissions or pay penalties. One possibility for carbondioxide sequestration is its fixation in microalgae. Microalgae can sequester CO2 from flue gases emitted from fossil fuel-fired refinery plants and units, thereby reducing emissions of a major greenhouse ga...

Full Text Available The possibility of use of carbondioxide in gas storage processes is presented. The model of mixing process between CO2 and methane in porous media is given. The process of injection of carbondioxide into a lower part of storage near the water –gas contact is modeled. The example of changes in the mixing zone is presented and discussed.

Studies pertaining to the effects of economic growth on the environment generally focused on diverse relationships between carbondioxide, economic growth and energy consumption.This paper contributes to the literature by determining the effects of the US and China’s emissions on several economies carbondioxide discharges from 1960 to 2010. The analysis uses a cointegration procedure proposed by Saikkonen and Lütkepohl. The study further applies the Granger causality test to test for causal...

A system is provided that substantially increases the efficiency of CO.sub.2 capture and removal by positioning a catalyst within an optimal distance from the air-liquid interface. The catalyst is positioned within the layer determined to be the highest concentration of carbondioxide. A hydrophobic tether is attached to the catalyst and the hydrophobic tether modulates the position of the catalyst within the liquid layer containing the highest concentration of carbondioxide.

The electrochemical conversion of carbondioxide and water into useful products is a major challenge in facilitating a closed carbon cycle. Here we report a cobalt protoporphyrin immobilized on a pyrolytic graphite electrode that reduces carbondioxide in an aqueous acidic solution at relatively low

A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbondioxide. The developed catalyst activates carbondioxide and delivers over 16% yield of DMC without the use of any dehydra...

The feasibility of using carbondioxide as feedstock in precast concrete production is studied. Carbondioxide reacts with calcium compounds in concrete, producing solid calcium carbonates in binding matrix. Two typical precast products are examined for their capacity to store carbondioxide during the production. They are concrete blocks and fiber-cement panels. The two products are currently mass produced and cured by steam. Carbondioxide can be used to replace steam in curing process to accelerate early strength, improve the long-term durability and reduce energy and emission. For a reaction within a 24-hour process window, the theoretical maximum possible carbon uptake in concrete is found to be 29% based on cement mass in the product. To reach the maximum uptake, a special process is developed to promote the reaction efficiency to 60-80% in 4-hour carbondioxide curing and improve the resistance to freeze-thaw cycling and sulfate ion attack. The process is also optimized to meet the project target of $10/tCO2 in carbon utilization. By the use of self-concentrating absorption technology, high purity CO2 can be produced at a price below $40/t. With low cost CO2 capture and utilization technologies, it is feasible to establish a network for carbon capture and utilization at the vicinity of carbon sources. If all block produces and panel producers in United States could adopt carbondioxide process in their production in place of steam, carbon utilization in these two markets alone could consume more than 2 Mt CO2/year. This capture and utilization process can be extended to more precast products and will continue for years to come.

In textile industry, supercritical carbondioxide (scCO2), possessing liquid-like densities, mostly find an application on textile dyeing processes such as providing hydrophobic dyes an advantage on dissolving. Their gas-like low viscosities and diffusion properties can result in shorter dyeing periods in comparison with the conventional water dyeing process. Supercritical carbondioxide dyeing is an anhydrous dyeing and this process comprises the usage of less energy and chemicals when compared to conventional water dyeing processes leading to a potential of up to 50% lower operation costs. The advantages of supercritical carbondioxide dyeing method especially on synthetic fiber fabrics hearten leading textile companies to alter their dyeing method to this privileged waterless dyeing technology. Supercritical carbondioxide (scCO2) waterless dyeing is widely known and applied green method for sustainable and eco-friendly textile industry. However, not only the dyeing but also scouring, desizing and different finishing applications take the advantage of supercritical carbondioxide (scCO2). In this review, not only the principle, advantages and disadvantages of dyeing in supercritical carbondioxide but also recent developments of scCO2 usage in different textile processing steps such as scouring, desizing and finishing are explained and commercial developments are stated and summed up.

This invention relates to high molecular weight terpolymer of ethylene, sulfur dioxide and carbon monoxide stable to 280/sup 0/C and containing as little as 36 mo1% ethylene and about 41 to 51 mo1% sulfur dioxide, and to the method of producing said terpolymer by irradiation of a liquid and gaseous mixture of ethylene, sulfur dioxide and carbon monoxide by means of Co-60 gamma rays or an electron beam, at a temperature of about 10 to 50/sup 0/C, and at a pressure of about 140 to 680 atmospheres, to initiate polymerization.

As the main greenhouse gas, CO 2 is considered as a threat in the context of global warming. Many available technologies to reduce CO 2 emission was about CO 2 separation from coal combustion and geological sequestration. However, how to deal with the cost-effective storage of CO 2 has become a new challenge. Moreover, chromium pollution, the treatment of which requires huge energy consumption, has attracted people's widespread attention. This study is aimed to develop the sequestration of CO 2 via chromium slag. A dynamic leaching experiment of chromium slag was designed to testify the ability of CO 2 adsorption onto chromium slag and to release Cr(VI) for stabilization. The results showed that the accumulative amounts of Cr(VI) were ca. 2.6 mg/g released from the chromium slag after 24 h of leaching. In addition, ca. 89 mg/g CO 2 was adsorbed by using pure CO 2 in the experiment at 12 h. Calcite is the only carbonate species in the post-carbonated slag analyzed by powder X-ray diffraction and thermal analysis. The approach provides the feasibility of the utilization of chromium slag and sequestration of the carbondioxide at the same time at ordinary temperatures and pressures.

Converting carbondioxide to useful chemicals in a selective and efficient manner remains a major challenge in renewable and sustainable energy research. Silver is an interesting electrocatalyst owing to its capability of converting carbondioxide to carbon monoxide selectively at room temperature; however, the traditional polycrystalline silver electrocatalyst requires a large overpotential. Here we report a nanoporous silver electrocatalyst that is able to electrochemically reduce carbondioxide to carbon monoxide with approximately 92% selectivity at a rate (that is, current) over 3,000 times higher than its polycrystalline counterpart under moderate overpotentials of high activity is a result of a large electrochemical surface area (approximately 150 times larger) and intrinsically high activity (approximately 20 times higher) compared with polycrystalline silver. The intrinsically higher activity may be due to the greater stabilization of CO2 - intermediates on the highly curved surface, resulting in smaller overpotentials needed to overcome the thermodynamic barrier.

Converting carbondioxide to useful chemicals in a selective and efficient manner remains a major challenge in renewable and sustainable energy research. Silver is an interesting electrocatalyst owing to its capability of converting carbondioxide to carbon monoxide selectively at room temperature; however, the traditional polycrystalline silver electrocatalyst requires a large overpotential. Here we report a nanoporous silver electrocatalyst that is able to electrochemically reduce carbondioxide to carbon monoxide with approximately 92% selectivity at a rate (that is, current) over 3,000 times higher than its polycrystalline counterpart under moderate overpotentials of high activity is a result of a large electrochemical surface area (approximately 150 times larger) and intrinsically high activity (approximately 20 times higher) compared with polycrystalline silver. The intrinsically higher activity may be due to the greater stabilization of CO2 (-) intermediates on the highly curved surface, resulting in smaller overpotentials needed to overcome the thermodynamic barrier.

Achieving a long-term food security and preventing hunger include a better nutrition through sustainable systems of production, distribution, and consumption. Nonetheless, the quest for an alternative to increasing global food supply to meet the growing demand has led to the use of poor agricultural practices that promote climate change. Given the contribution of the agricultural ecosystem towards greenhouse gas (GHG) emissions, this study investigated the causal nexus between carbondioxide emissions and agricultural ecosystem by employing a data spanning from 1961 to 2012. Evidence from long-run elasticity shows that a 1 % increase in the area of rice paddy harvested will increase carbondioxide emissions by 1.49 %, a 1 % increase in biomass-burned crop residues will increase carbondioxide emissions by 1.00 %, a 1 % increase in cereal production will increase carbondioxide emissions by 1.38 %, and a 1 % increase in agricultural machinery will decrease carbondioxide emissions by 0.09 % in the long run. There was a bidirectional causality between carbondioxide emissions, cereal production, and biomass-burned crop residues. The Granger causality shows that the agricultural ecosystem in Ghana is sensitive to climate change vulnerability.

Acute respiratory distress syndrome (ARDS) has a substantial mortality rate and annually affects more than 140,000 people in the USA alone. Standard management includes lung protective ventilation but this impairs carbondioxide clearance and may lead to right heart dysfunction or increased intracranial pressure. Extracorporeal carbondioxide removal has the potential to optimize lung protective ventilation by uncoupling oxygenation and carbondioxide clearance. The aim of this article is to review the carbondioxide removal strategies that are likely to be widely available in the near future. Relevant published literature was identified using PubMed and Medline searches. Queries were performed by using the search terms ECCOR, AVCO2R, VVCO2R, respiratory dialysis, and by combining carbondioxide removal and ARDS. The only search limitation imposed was English language. Additional articles were identified from reference lists in the studies that were reviewed. Several novel strategies to achieve carbondioxide removal were identified, some of which are already commercially available whereas others are in advanced stages of development.

Astronauts undergo CO2 exposure training to recognize their symptoms that can arise acutely both on the ground and in spaceflight. This article describes acute CO2 exposure training at NASA and examines the symptoms reported by astronauts during training. In a controlled training environment, astronauts are exposed to up to 8% CO2 (60 mmHg) by a rebreathing apparatus. Symptoms are reported using a standard form. Symptom documentation forms between April 1994 and February 2012 were obtained for 130 astronauts. The number of symptoms reported per session out of the possible 24 was related to age and sex, with those older slightly more likely to report symptoms. Women reported more symptoms on average than men (men: 3.7, women: 4.7). Respiratory symptoms (90%), flushing sensation/sweating (56%), and dizziness/feeling faint/lightheadedness (43%) were the top symptoms. Only headache reached statistical significance in differences between men (13%) and women (37%) after adjustment for multiple testing. Among those with multiple training sessions, respiratory symptoms were the most consistently reported. CO2 exposure training is an important tool to educate astronauts about their potential acute CO2 symptoms. Wide interindividual and temporal variations were observed in symptoms reported during astronaut CO2 exposure training. Headache could not be relied on as a marker of acute exposure during testing since fewer than half the subjects reported it. Our results support periodic refresher training since symptoms may change over time. Further study is needed to determine the optimal interval of training to maximize symptom recognition and inform operational decisions.Law J, Young M, Alexander D, Mason SS, Wear ML, Méndez CM, Stanley D, Meyers Ryder V, Van Baalen M. Carbondioxide physiological training at NASA. Aerosp Med Hum Perform. 2017; 88(10):897-902.

A molten metal reactor for converting a carbon material and steam into a gas comprising hydrogen, carbon monoxide, and carbondioxide is disclosed. The reactor includes an interior crucible having a portion contained within an exterior crucible. The interior crucible includes an inlet and an outlet; the outlet leads to the exterior crucible and may comprise a diffuser. The exterior crucible may contain a molten alkaline metal compound. Contained between the exterior crucible and the interior crucible is at least one baffle.

The use of a high velocity stream of carbondioxide snowflakes to clean large optics is well known, and has gained widespread acceptance in the astronomical community as a telescope maintenance technique. Ultimately, however, the success of carbondioxide snow cleaning depends on the availability of high purity carbondioxide. The higher the purity of the carbondioxide, the longer will be the time interval between required mirror washings. The highest grades of commercially produced liquid carbondioxide are often not available in the more remote regions of the world - such as where major astronomical observatories are often located. Furthermore, the purity of even the highest grades of carbondioxide are only nominal, and wide variations are known to occur from tank to tank. Occasionally, visible deposits of organic impurities are left behind during cleaning with carbondioxide that is believed to be 99.999% pure. A zeolite molecular sieve based filtration system has proven to be very effective in removing these organic impurities. A zeolite is a complex alumino-silicate. One example has an empirical formula of Na2O(Al2O3)(SiO2)2yH2O, where y=0 to 8. The zeolites have an open crystal structure and are capable of trapping impurities like 8-methylheptadecane (an oil) and 2,6-octadine-1-ol,3,7- dimethyl-,(E)- (a fatty acid). In fact, a zeolite can trap 29.5% of its own weight in SAE 20 lubricant at 25 degree(s)C. After filtration of liquid CO2 through zeolites, the concentration of measured impurities was below the detection limit for state-of-the-art gas chromatography systems.

Variability of dissolved inorganic carbon (DIC) and the fugacity of carbondioxide (fCO2) is discussed for tropical East Atlantic surface waters in October–November 1993 and May–June 1994. High precipitation associated with the Intertropical Convergence Zone, river input and equatorial upwelling

Discusses the use of ratio diagrams, which plot the calculations of equilibrium concentrations of the species of the carbonate system. Provides examples to describe how these diagrams can be used to illustrate the behavior systems of interest in volumetric analysis, where absorption or loss of carbondioxide takes place. (TW)

Purpose: The purpose of this paper is to assess the carbondioxide emissions associated with electric, HVAC, and hot water use from a US university. Design/methodology/approach: First, the total on-campus electrical, natural gas and oil consumption for an entire year was assessed. For each category of energy use, the carbon associated with…

An experiment was conducted for generating high-frequency plasma in supercritical carbondioxide; it is expected to have the potential for applications in various types of practical processes. It was successfully generated at 6-20 MPa using electrodes mounted in a supercritical cell with a gap of 1 mm. Emission spectra were then measured to investigate the physical properties of supercritical carbondioxide plasma. The results indicated that while the emission spectra for carbondioxide and carbon monoxide could be mainly obtained at a low pressure, the emission spectra for atomic oxygen could be obtained in the supercritical state, which increased with the pressure. The temperature of the plasma in supercritical state was estimated to be approximately 6000-7000 K on the assumption of local thermodynamic equilibrium and the calculation results of thermal equilibrium composition in this state showed the increase of atomic oxygen by the decomposition of CO 2

The interaction of carbondioxide and erbium thin films is characterized for temperatures in the region of 300 to 900 0 C and partial pressure of carbondioxide near 5 x 10 -7 Torr. Dynamic film pumping speeds were measured against a mercury diffusion pump of known pumping speed and conductance. A quadrupole mass spectrometer was used to monitor the carbondioxide flow which originated from a calibrated leak in the 10 -6 standard cm 3 /s range. Data reduction was via a dedicated minicomputer with associated printer/plotter. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C. The reaction was preceded by the desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface

The seasonal cycle of the globally averaged atmospheric carbondioxide concentrations results from the seasonal changes in the gas exchange between the atmosphere and other carbon pools. Terrestrial pools are the most important. Boreal and temperate ecosystems provide a sink for carbondioxide only during the warm period of the year, and, therefore, the summertime reduction in the atmospheric carbondioxide concentration is usually explained by the seasonal changes in the magnitude of terrestrial carbon sink. Although this explanation seems almost obvious, it is surprisingly difficult to support it by calculations of the seasonal changes in the strength of the sink provided by boreal and temperate ecosystems. The traditional conceptual framework for modelling net ecosystem exchange (NEE) leads to the estimates of the NEE seasonal cycle amplitude which are too low for explaining the amplitude of the seasonal cycle of the atmospheric carbondioxide concentration. To propose a more suitable conceptual framework we develop a model ensemble that consists of nine structurally different models and covers various approaches to modelling gross primary production and heterotrophic respiration, including the effects of light saturation, limited light use efficiency, limited water use efficiency, substrate limitation and microbiological priming. The use of model ensembles is a well recognized methodology for evaluating structural uncertainty of model-based predictions. In this study we use this methodology for exploratory modelling analysis - that is, to identify the mechanisms that cause the observed amplitude of the seasonal cycle of the atmospheric carbondioxide concentration and its slow but steady growth.

Injection of carbondioxide (CO2) into saline aquifers has been proposed as a means to reduce greenhouse gas emissions (geological carbon sequestration). Large-scale injection of CO2 will induce a variety of coupled physical and chemical processes, including multiphase fluid flow, fluid pressurization and changes in effective stress, solute transport, and chemical reactions between fluids and formation minerals. This work addresses some of these issues with special emphasis given to the physics of fluid flow in brine formations. An investigation of the thermophysical properties of pure carbondioxide, water and aqueous solutions of CO2 and NaCl has been conducted. As a result, accurate representations and models for predicting the overall thermophysical behavior of the system CO2-H2O-NaCl are proposed and incorporated into the numerical simulator TOUGH2/ECO2. The basic problem of CO2 injection into a radially symmetric brine aquifer is used to validate the results of TOUGH2/ECO2. The numerical simulator has been applied to more complex flow problem including the CO2 injection project at the Sleipner Vest Field in the Norwegian sector of the North Sea and the evaluation of fluid flow dynamics effects of CO2 injection into aquifers. Numerical simulation results show that the transport at Sleipner is dominated by buoyancy effects and that shale layers control vertical migration of CO2. These results are in good qualitative agreement with time lapse surveys performed at the site. High-resolution numerical simulation experiments have been conducted to study the onset of instabilities (viscous fingering) during injection of CO2 into saline aquifers. The injection process can be classified as immiscible displacement of an aqueous phase by a less dense and less viscous gas phase. Under disposal conditions (supercritical CO2) the viscosity of carbon

A trap is described that removes the nitrogen oxides from ( 11 C)carbondioxide. This improves the yields of the subsequent reactions of the carbondioxide and permits the use of much smaller amounts of reagents, which should improve the specific activities of the final products. (author)

Global airlines consume over 5 million barrels of oil per day, and the resulting carbondioxide (CO2) emitted by aircraft engines is of concern. This article provides a contemporary review of the literature associated with the measures available to the civil aviation industry for mitigating CO2 emissions from aircraft. The measures are addressed under two categories - policy and legal-related measures, and technological and operational measures. Results of the review are used to develop several insights into the challenges faced. The analysis shows that forecasts for strong growth in air-traffic will result in civil aviation becoming an increasingly significant contributor to anthropogenic CO2 emissions. Some mitigation-measures can be left to market-forces as the key-driver for implementation because they directly reduce airlines' fuel consumption, and their impact on reducing fuel-costs will be welcomed by the industry. Other mitigation-measures cannot be left to market-forces. Speed of implementation and stringency of these measures will not be satisfactorily resolved unattended, and the current global regulatory-framework does not provide the necessary strength of stewardship. A global regulator with ‘teeth' needs to be established, but investing such a body with the appropriate level of authority requires securing an international agreement which history would suggest is going to be very difficult. If all mitigation-measures are successfully implemented, it is still likely that traffic growth-rates will continue to out-pace emissions reduction-rates. Therefore, to achieve an overall reduction in CO2 emissions, behaviour change will be necessary to reduce demand for air-travel. However, reducing demand will be strongly resisted by all stakeholders in the industry; and the ticket price-increases necessary to induce the required reduction in traffic growth-rates place a monetary-value on CO2 emissions of approximately 7-100 times greater than other common

Extrapolation of world energy consumption between 1990 and 2007 to the future reveals the complete exhaustion of petroleum, natural gas, uranium and coal reserves on Earth in 2040, 2044, 2049 and 2054, respectively. We are proposing global carbondioxide recycling to use renewable energy so that all people in the whole world can survive. The electricity will be generated by solar cell in deserts and used to produce hydrogen by seawater electrolysis at t nearby desert coasts. Hydrogen, for which no infrastructures of transportation and combustion exist, will be converted to methane at desert coasts by the reaction with carbondioxide captured by energy consumers. Among systems in global carbondioxide recycling, seawater electrolysis and carbondioxide methanation have not been performed industrially. We created energy-saving cathodes for hydrogen production and anodes for oxygen evolution without chlorine formation in seawater electrolysis, and ideal catalysts for methane formation by the reaction of carbondioxide with hydrogen. Prototype plant and industrial scale pilot plant have been built.

Volcanic degassing of carbondioxide plays an important role in keeping the atmosphere-ocean portion of the carbon geochemical cycle in balance. The atmosphere-ocean carbon deficit requires replenishment of 6??1012 mol CO2/yr, and places an upper limit on the output of carbondioxide from volcanoes. The CO2 output of the global mid-oceanic ridge system is ca. 0.7??1012 mol/yr, thus supplying only a fraction of the amount needed to balance the carbon deficit. The carbondioxide flux from subaerial volcanoes is poorly known, but it appears to be at least as large as the mid-oceanic ridge flux. Much (perhaps most) of the CO2 emitted from volcanoes is degassed noneruptively. This mode of degassing may lead to impacts on the environment and biosphere that are fundamentally different in character from those envisioned in published scenarios, which are based on the assumption that CO2 degassing occurs predominantly by eruptive processes. Although the flux of carbondioxide from volcanoes is poorly constrained at present, it is clearly two orders of magnitude lower than the anthropogenic output of CO2.

Plane-wave density functional theory (DFT) calculations were performed to simulate water and carbondioxide adsorption at the (010) surface of five olivine minerals, namely, forsterite (Mg2SiO4), calcio-olivine (Ca2SiO4), tephroite (Mn2SiO4), fayalite (Fe2SiO4), and Co-olivine (Co2SiO4). Adsorption energies per water molecule obtained from energy minimizations varied from -78 kJ mol-1 for fayalite to -128 kJ mol-1 for calcio-olivine at sub-monolayer coverage and became less exothermic as coverage increased. In contrast, carbondioxide adsorption energies at sub-monolayer coverage ranged from -20 kJ mol-1 for fayalite to -59 kJ mol-1 for calcio-olivine. Therefore, the DFT calculations show a strong driving force for carbondioxide displacement by water at the surface of all olivine minerals in a competitive adsorption scenario. Additionally, adsorption energies for both water and carbondioxide were found to be more exothermic for the alkaline-earth (AE) olivines than for the transition-metal (TM) olivines and to not correlate with the solvation enthalpies of the corresponding divalent cations. However, a correlation was obtained with the charge of the surface divalent cation indicating that the more ionic character of the AE cations in the olivine structure relative to the TM cations leads to greater interactions with adsorbed water and carbondioxide molecules at the surface and thus more exothermic adsorption energies for the AE olivines. For calcio-olivine, which exhibits the highest divalent cation charge of the five olivines, ab initio molecular dynamics simulations showed that this effect leads both water and carbondioxide to react with the surface and form hydroxyl groups and a carbonate-like species, respectively.

The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates, through reaction with carbondioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. This quarter, electrobalance tests conducted at LSU indicated that exposure of sorbent to water vapor prior to contact with carbonation gas does not significantly increase the reaction rate. Calcined fine mesh trona has a greater initial carbonation rate than calcined sodium bicarbonate, but appears to be more susceptible to loss of reactivity under severe calcination conditions. The Davison attrition indices for Grade 5 sodium bicarbonate, commercial grade sodium carbonate and extra fine granular potassium carbonate were, as tested, outside of the range suitable for entrained bed reactor testing. Fluidized bed testing at RTI indicated that in the initial stages of reaction potassium carbonate removed 35% of the carbondioxide in simulated flue gas, and is reactive at higher temperatures than sodium carbonate. Removals declined to 6% when 54% of the capacity of the sorbent was exhausted. Carbonation data from electrobalance testing was correlated using a shrinking core reaction model. The activation energy of the reaction of sodium carbonate with carbondioxide and water vapor was determined from nonisothermal thermogravimetry

As a carbon-based life form living in a predominantly carbon-based environment, it is not surprising that we have created a carbon-based consumer society. Our principle sources of energy are carbon-based (coal, oil, and gas) and many of our consumer goods are derived from organic (i.e., carbon-based) chemicals (including plastics, fabrics and materials, personal care and cleaning products, dyes, and coatings). Even our large-volume inorganic-chemicals-based industries, including fertilizers and construction materials, rely on the consumption of carbon, notably in the form of large amounts of energy. The environmental problems which we now face and of which we are becoming increasingly aware result from a human-induced disturbance in the natural carbon cycle of the Earth caused by transferring large quantities of terrestrial carbon (coal, oil, and gas) to the atmosphere, mostly in the form of carbondioxide. Carbon is by no means the only element whose natural cycle we have disturbed: we are transferring significant quantities of elements including phosphorus, sulfur, copper, and platinum from natural sinks or ores built up over millions of years to unnatural fates in the form of what we refer to as waste or pollution. However, our complete dependence on the carbon cycle means that its disturbance deserves special attention, as is now manifest in indicators such as climate change and escalating public concern over global warming. As with all disturbances in materials balances, we can seek to alleviate the problem by (1) dematerialization: a reduction in consumption; (2) rematerialization: a change in what we consume; or (3) transmaterialization: changing our attitude towards resources and waste. The "low-carbon" mantra that is popularly cited by organizations ranging from nongovernmental organizations to multinational companies and from local authorities to national governments is based on a combination of (1) and (2) (reducing carbon consumption though greater

Over the last century, man's activities on earth have sent off trace gases into the planet's atmosphere that have been concentrating to a level posing a threat to the global climate. Since scientists particularly spotted carbondioxide as the main contributor to what we now call the greenhouse effect, there is urgent need for measures reducing carbondioxide emission worldwide, may be on the basis of a global convention to be signed by both the industrialised and the developing countries. The industrialised countries, which certainly are the main pollutors, also will have the technological and financial resources to respond to the challenge of global warning more directly and faster than the developing countries. The power industry's management in the FRG is taking the problem seriously and has already come out with strategies for curbing carbondioxide emissions from fossil-fuel power plant. (orig.) [de

Background. In premature infants, maintaining blood partial pressure of carbondioxide (pCO2) value within a narrow range is important to avoid cerebral lesions. The aim of this study was to assess the accuracy of a noninvasive transcutaneous method (TcpCO2), compared to blood partial pressure of carbondioxide (pCO2). Methods. Retrospective observational study in a tertiary neonatal intensive care unit. We analyzed the correlation between blood pCO2 and transcutaneous values and the accuracy...

This paper is an actor-network theory-based analysis of the hindrances for implementation of carbondioxide capture, transport and storage, CCS, as a climate mitigation initiative in Norway. It uses the Norwegian projects Kårstø, Mongstad, Tjeldbergodden/Halten/Draugen, Sleipner and Snøhvit as the basis for a discussion of the relevant technologies, obstacles, policies, rhetoric and realities. CCS is a possible way to reduce emissions of carbondioxide. We need an emission reduction of th...

Carbondioxide is the main greenhouse gas and its major source is combustion of fossil fuels for power generation. The objective of this study is to carry out the steady-state sensitivity analysis for chemical absorption of carbondioxide capture from flue gas using monoethanolamine solvent. First...... performance of the process to the L/G ratio to the absorber, CO2 lean solvent loadings, and striper pressure are presented in this paper. Based on the sensitivity analysis process optimization problems have been defined and solved and, a preliminary control structure selection has been made....

In order to obtain basic knowledge on the increased giving of carbondioxide to vegetables, the carbondioxide environment in growing houses was analyzed, and the physiological and ecological properties of vegetables cultivated in carbondioxide environment were elucidated. To improve the carbondioxide environment, giving increased quantity of carbondioxide, air flow, ventilation, and others were examined. The concentration of carbondioxide began to decrease when the illumination intensity on growing layer reached 1 -- 1.5 lux, owing to the photo-synthetic activity of vegetables, and decreased rapidly at 3 -- 5 lux. The lowering of carbondioxide concentration lowered the photo-synthesis of vegetables extremely, and the transfer of synthesized carbohydrate to roots was obstructed. The effect suffered in low carbondioxide concentration left some aftereffect even after ventilation and the recovery of carbondioxide concentration. But this aftereffect was not observed in case of cucumber. To improve carbondioxide environment, the air flow or ventilation required for minimizing the concentration lowering was determined, but giving increased quantity of carbondioxide was most effective. The interaction of carbondioxide concentration and light was examined regarding the effect on photo-synthesis, and some knowledge of practical application was obtained. The effect of giving more carbondioxide was more remarkable as the treatment was given to younger seedlings and in the period when the capacity of absorbing assimilation products was higher. (Kako, I.)

Full Text Available The Thetford Project (1968–1976 was a keystone project for the newly established Institute of Hydrology. Its primary objective was to elucidate the processes underlying evaporation of transpired water and intercepted rainfall from plantation forest, so as to explain hydrological observations that more water was apparently returned to the atmosphere from plantations than from grassland and heathland. The primary approach was to determine the fluxes of water vapour from a stand of Scots pine, situated within a larger area of plantations of Scots and Corsican pine, in Thetford Forest, East Anglia, UK, using the Bowen ratio approach. In 1976, advantage was taken of the methodology developed to add measurement of profiles of carbondioxide concentration so as to enable the fluxes of CO2 also to be calculated. A team from Aberdeen and Edinburgh Universities collected 914 hours of 8-point CO2 concentration profiles, largely between dawn and dusk, on days from March to October, and the data from an "elite" data set of 710 hours have been analysed. In conditions of moderate temperature (−1 with high solar irradiance (>500 W m−2, CO2 uptake reached relatively high rates for pine of up to 20 µmol m−2 s−1 in the middle of the day. This rate of CO2 uptake is higher than has been recently found for four Scots pine forests in continental Europe during July 1997. However, the year of 1976 was exceptionally hot and dry, with air temperatures reaching 30°C and the water deficit in the top 3 m of soil at the site of 152 mm by August. Air temperatures of over 25°C led to large specific humidity deficits, approaching 20 g kg−1, and associated severe reductions in CO2 uptake, as well as in evaporation. However, when specific humidity deficits dropped below c. 15 g kg−1 on succeeding days, generally as a result of lower air temperatures rather than lower solar irradiance, there was rapid recovery in both uptake and evaporation, thus indicating that

The adequacy of assumptions required to project atmospheric CO 2 concentrations in time frames of practical importance is reviewed. Relevant issues concern the form assumed for future fossil fuel release, carbon cycle approximations, and the implications of revisions in fossil fuel patterns required to maintain atmospheric CO 2 levels below a chosen threshold. In general, we find that with a judiciously selected exponential fossil fuel release rate, and with a constant airborn fraction, we can estimate atmospheric CO 2 growth over the next 50 years based on essentially surprise free scenarios. Resource depletion effects must be included for projections beyond about 50 years, and on this time frame the constant airborne fraction approximation has to be questioned as well (especially in later years when the fossil fuel use begins to taper off). For projections for over 100 years, both energy demand scenarios and currently available carbon cycle models have sufficient uncertainties that atmospheric CO 2 levels derived from them are not much better than guesses

This study was directed to finding an optimum extraction condition of genistein from the S. flavescens with supercritical carbondioxide as a solvent. In this effort, effects of the extraction conditions including pressure, temperature and a co-solvent on the extraction efficiency were investigated. The aqueous ethanol and methanol solutions were used as co-solvents while the tested operating pressure and temperature ranges were from 200 bar to 300 bar and from 308.15 K to 323.15 K, respectively. The concentration of genistein was determined by means of HPLC equipped with a UV detector. From the results, it was observed that an increase in pressure led to the higher extraction efficiency. Further, methanol showed better performance as a co-solvent than ethanol. The DPPH radical scavenging activities were measured to compare antioxidant activities of S. flavescens extracts.

Rising concentrations of atmospheric carbondioxide ([CO2]) and subsequent changes in climate, including temperature and precipitation extremes, are very likely to alter pest pressures in both managed and unmanaged plant communities. Such changes in pest pressures can be positive (migration from a region) or negative (new introductions), but are likely to be accompanied by significant economic and environmental consequences. Recent studies indicate the range of invasive weeds such as kudzu and insects such as mountain pine beetle have already expanded to more northern regions as temperatures have risen. To reduce these consequences, a better understanding of the link between CO2/climate and pest biology is needed in the context of existing and new strategies for pest management. This paper provides an overview of the probable biological links and the vulnerabilities of existing pest management (especially chemical control) and provides a preliminary synthesis of research needs that could potentially improve the ability to monitor, mitigate, and manage pest impacts.

A recent version of the Boreal Ecosystem Productivity Simulator (BEPS) was extended and modified to include northern peatlands. This thesis evaluated the BEPS-TerrainLab using observations made at the Mer Bleue bog located near Ottawa, Ontario, and the Sandhill fen located near Prince Albert, Saskatchewan. The code was revised to represent the multi-layer canopy and processes related to energy, water vapour and carbondioxide fluxes through remotely-sensed leaf area index (LAI) maps. A quick and reliable method was also developed to determine shrub LAI with the LAI-2000 plant canopy analyzer. A large number of LAI data was collected at the Mer Bleue bog for the development of a new remote sensing-based methodology using multiple end member spectral unmixing to allow for separate tree and shrub LAI mapping in ombrotrophic peatlands. The methodology was also adapted for use in minerotrophic peatlands and their surrounding landscapes. These LAI maps within the BEPS-TerrainLab represented the tree and shrub layers of the Mer Bleue bog and the tree and shrub/sedge layers of the Sandhill fen. The study examined the influence of mesoscale topography (Mer Bleue bog) and macro- and mesoscale topography (Sandhill fen) on wetness, evapotranspiration, and gross primary productivity during the snow-free period of 2004. The results suggested that a peatland type-specific differentiation of macro- and mesoscale topographic effects on hydrology should be included in future peatland ecosystem modelling efforts in order to allow for a more realistic simulation of the soil water balance in peatlands and to reduce uncertainties in carbondioxide and methane annual fluxes from wetlands.

Carbondioxide is the main atmospheric greenhouse gas released from industrial point sources. In order to mitigate adverse environmental effects of these emissions, carbon capture, storage and utilization is required. To this end, several CO2 capture technologies are being developed for application in carbon capture, which include aqueous amines and water-lean solvents. Herein we report new aminopyridine solvents with the potential for CO2 capture from coal-fired power plants. These four solvents 2-picolylamine, 3-picolylamine, 4-picolylamine and N’-(pyridin-4-ylmethyl)ethane-1,2-diamine are liquids that rapidly bind CO2 to form crystalline solids at standard room temperature and pressure. These solvents have displayed high CO2 capture capacity (11 - 20 wt%) and can be regenerated at temperatures in the range of 120 - 150 C. The advantage of these primary aminopyridine solvents is that crystalline salt product can be separated, making it possible to regenerate only the CO2-rich solid ultimately resulting in reduced energy penalty.

Diminishing supplies of conventional energy sources and growing concern over greenhouse gas emissions present significant challenges to supplying the world's rapidly increasing demand for energy. The electrochemical reduction of carbondioxide has the potential to address many of these issues by providing a means of storing electricity in chemical form. Storing electrical energy as chemicals is beneficial for leveling the output of clean, but intermittent renewable energy sources such as wind and solar. Electrical energy stored as chemicals can also be used as carbon neutral fuels for portable applications allowing petroleum derived fuels in the transportation sector to be replaced by more environmentally friendly energy sources. However, to be a viable technology, the electrochemical reduction of carbondioxide needs to have both high current densities and energetic efficiencies (Chapter 1). Although many researchers have studied the electrochemical reduction of CO2 including parameters such as catalysts, electrolytes and temperature, further investigation is needed to improve the understanding of this process and optimize the performance (Chapter 2). This dissertation reports the development and validation of a microfluidic reactor for the electrochemical reduction of CO2 (Chapter 3). The design uses a flowing liquid electrolyte instead of the typical polymer electrolyte membrane. In addition to other benefits, this flowing electrolyte gives the reactor great flexibility, allowing independent analysis of each electrode and the testing of a wide variety of conditions. In this work, the microfluidic reactor has been used in the following areas: • Comparison of different metal catalysts for the reduction of CO2 to formic acid and carbon monoxide (Chapter 4). • Investigation of the effects of the electrolyte pH on the reduction of CO2 to formic acid and carbon monoxide (Chapter 5). • Study of amine based electrolytes for lowering the overpotentials for CO2

Compacted pellets of uranium oxide alone or containing one or more additives such as plutonium dioxide, gadolinium oxide, titanium dioxide, silica, and alumina are heated to 900 to 1599 0 C in the presence of a mixture of hydrogen and carbondioxide, either alone or with an inert carrier gas and held at the desired temperature in this atmosphere to sinter the pellets. The sintered pellets are then cooled in an atmosphere having an oxygen partial pressure of 10 -4 to 10 -18 atm of oxygen such as dry hydrogen, wet hydrogen, dry carbon monoxide, wet carbon monoxide, inert gases such as nitrogen, argon, helium, and neon and mixtures of ayny of the foregoing including a mixture of hydrogen and carbondioxide. The ratio of hydrogen to carbondioxide in the gas mixture fed to the furnace is controlled to give a ratio of oxygen to uranium atoms in the sintered particles within the range of 1.98:1 to about 2.10:1. The water vapor present in the reaction products in the furnace atmosphere acts as a hydrolysis agent to aid removal of fluoride should such impurity be present in the uranium oxide. (U.S.)

National Aeronautics and Space Administration — Our approach to high-pressure carbondioxide storage will directly address the challenges associated with storage of compressed carbondioxide - the need to reduce...

Standardized terms structured to allow consistent machine storage and retrieval of information pertaining to carbondioxide and the environment are included in this thesaurus. Although terminology is based on the Energy Data Base Subject Thesaurus used by the Technical Information Center in indexing information of importance to the DOE mission, additional terms highly specific to the CO 2 literature are also included

Electrobalance studies of calcination and carbonation of sodium bicarbonate materials were conducted at Louisiana State University. Calcination in an inert atmosphere was rapid and complete at 120 C. Carbonation was temperature dependent, and both the initial rate and the extent of reaction were found to decrease as temperature was increased between 60 and 80 C. A fluidization test apparatus was constructed at RTI and two sodium bicarbonate materials were fluidized in dry nitrogen at 22 C. The bed was completely fluidized at between 9 and 11 in. of water pressure drop. Kinetic rate expression derivations and thermodynamic calculations were conducted at RTI. Based on literature data, a simple reaction rate expression, which is zero order in carbondioxide and water, was found to provide the best fit against reciprocal temperature. Simulations based on process thermodynamics suggested that approximately 26 percent of the carbondioxide in flue gas could be recovered using waste heat available at 240 C.

Electrobalance studies of calcination and carbonation of sodium bicarbonate materials were conducted at Louisiana State University. Calcination in an inert atmosphere was rapid and complete at 120 C. Carbonation was temperature dependent, and both the initial rate and the extent of reaction were found to decrease as temperature was increased between 60 and 80 C. A fluidization test apparatus was constructed at RTI and two sodium bicarbonate materials were fluidized in dry nitrogen at 22 C. The bed was completely fluidized at between 9 and 11 in. of water pressure drop. Kinetic rate expression derivations and thermodynamic calculations were conducted at RTI. Based on literature data, a simple reaction rate expression, which is zero order in carbondioxide and water, was found to provide the best fit against reciprocal temperature. Simulations based on process thermodynamics suggested that approximately 26 percent of the carbondioxide in flue gas could be recovered using waste heat available at 240 C

In correlation to climate change and CO2 emission different campaigns highlight the importance of forests and trees to regulate the concentration of carbondioxide in the earths' atmosphere. Seeing millions of square miles of rainforest cut down every day, this is truly a valid point. Nevertheless, we often tend to forget what scientists like Spokes try to raise awareness for: The oceans - and foremost deep sea sections - resemble the second biggest deposit of carbondioxide. Here carbon is mainly found in form of carbonate and hydrogen carbonate. The carbonates are needed by corals and other sea organisms to maintain their skeletal structure and thereby to remain vital. To raise awareness for the protection of this fragile ecosystem in schools is part of our approach. Awareness is achieved best through understanding. Therefore, our approach is a hands-on activity that aims at showing students how the carbondioxide absorption changes in relation to the water temperature - in times of global warming a truly sensitive topic. The students use standard syringes filled with water (25 ml) at different temperatures (i.e. 10°C, 20°C, 40°C). Through a connector students inject carbondioxide (25ml) into the different samples. After a fixed period of time, students can read of the remaining amount of carbondioxide in relation to the given water temperature. Just as with every scientific project, students need to closely monitor their experiments and alter their setups (e.g. water temperature or acidity) according to their initial planning. A digital template (Excel-based) supports the analysis of students' experiments. Overview: What: hands-on, minds -on activity using standard syringes to exemplify carbondioxide absorption in relation to the water temperature (Le Chatelier's principle) For whom: adjustable from German form 11-13 (age: 16-19 years) Time: depending on the prior knowledge 45-60 min. Sources (extract): Spokes, L.: Wie Ozeane CO2 aufnehmen. Environmental

Full Text Available Background. In premature infants, maintaining blood partial pressure of carbondioxide (pCO2 value within a narrow range is important to avoid cerebral lesions. The aim of this study was to assess the accuracy of a noninvasive transcutaneous method (TcpCO2, compared to blood partial pressure of carbondioxide (pCO2. Methods. Retrospective observational study in a tertiary neonatal intensive care unit. We analyzed the correlation between blood pCO2 and transcutaneous values and the accuracy between the trends of blood pCO2 and TcpCO2 in all consecutive premature infants born at <33 weeks’ gestational age. Results. 248 infants were included (median gestational age: 29 + 5 weeks and median birth weight: 1250 g, providing 1365 pairs of TcpCO2 and blood pCO2 values. Pearson’s R correlation between these values was 0.58. The mean bias was −0.93 kPa with a 95% confidence limit of agreement of −4.05 to +2.16 kPa. Correlation between the trends of TcpCO2 and blood pCO2 values was good in only 39.6%. Conclusions. In premature infants, TcpCO2 was poorly correlated to blood pCO2, with a wide limit of agreement. Furthermore, concordance between trends was equally low. We warn about clinical decision-making on TcpCO2 alone when used as continuous monitoring.

The novel optical, electronic, and/or magnetic properties of metal and semiconductor nanoparticles have resulted in extensive research on new methods for their preparation. An ideal preparation method would allow the particle size, size distribution, crystallinity, and particle shape to be easily controlled, and would be applicable to a wide variety of material systems. Numerous preparation methods have been reported, each with its inherent advantages and disadvantages; however, an ideal method has yet to emerge. The most widely applied methods for nanoparticle preparation include the sonochemical reduction of organometallic reagents,(1&2) the solvothermal method of Alivisatos,(3) reactions in microemulsions,(4-6) the polyol method (reduction by alcohols),(7-9) and the use of polymer and solgel materials as hosts.(10-13) In addition to these methods, there are a variety of methods that take advantage of the unique properties of a supercritical fluid.(14&15) Through simple variations of temperature and pressure, the properties of a supercritical fluid can be continuously tuned from gas-like to liquid-like without undergoing a phase change. Nanoparticle preparation methods that utilize supercritical fluids are briefly reviewed below using the following categories: Rapid Expansion of Supercritical Solutions (RESS), Reactive Supercritical Fluid Processing, and Supercritical Fluid Microemulsions. Because of its easily accessible critical temperature and pressure and environmentally benign nature, carbondioxide is the most widely used supercritical solvent. Supercritical CO2 is unfortunately a poor solvent for many polar or ionic species, which has impeded its use in the preparation of metal and semiconductor nanoparticles. We have developed a reactive supercritical fluid processing method using supercritical carbondioxide for the preparation of metal and metal sulfide particles and used it to prepare narrowly distributed nanoparticles of silver (Ag) and silver sulfide

"NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" (NASA 2012). These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must not only blast out of earth's gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbondioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach, which is then implemented in a full-scale integrated atmosphere revitalization test. This paper describes the carbondioxide (CO2) removal hardware design and sorbent screening and characterization effort in support of the Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project within the AES program. A companion paper discusses development of atmosphere revitalization models and simulations for this project.

Carbondioxide conversion and utilization is gaining significant attention worldwide, not only because carbondioxide has an impact on global climate change, but also because it provides a source for potential fuels and chemicals. Methanol is an important fuel that can be obtained by the hydrogenation of carbondioxide. In this research, the modeling of a reactor to produce methanol using carbondioxide and hydrogen is carried out by way of an ANOVA and a central composite design. Reaction te...

that are emitted in Sweden as a result of Sweden's own productions when emissions connected to exports are subtracted. The calculations show that we may seriously underestimate emissions from imports when only Swedish emission data are used. A substantial part of the emissions caused by Sweden's imports occur within the European Union, almost 70 %. Other countries in the world with substantial emissions connected to Sweden's imports are Russia, Norway, China and United States. Imports of fossil fuels and electricity accounts for 17 % of the emissions of carbondioxide from the imports. Private households account for 87-89 percent of the carbondioxide emissions that are caused by end consumers in Sweden when products life cycles are considered. The public sector accounts for the remaining part. Further studies should seek to ameliorate the emission data from the main trading partners and include emissions of other greenhouse gases in addition to carbondioxide. The other greenhouse gases are foremost connected to the agricultural end energy sector

Proven approaches for reducing heat-trapping emissions are increasingly cost competitive and feasible at scale. Such approaches include renewable-energy technologies, energy efficiency, reduced deforestation, and abatement of industrial and agricultural emissions. Their pace of deployment, though, is far from sufficient to limit warming well below 2°C above preindustrial levels, the goal of the Paris Agreement. Against this backdrop, technologies for carbon removal are increasingly asserted as key to climate policy. Carbondioxide removal (CDR), or negative emissions, technologies can compensate for ongoing emissions, helping keep ambitious warming limits in reach. The dramatic rise of CDR approaches in analysis and planning towards ambitious climate goals, however, has stirred up discomfort and debate. Focusing on rightsizing CDR expectations, this presentation will first briefly reflect on the status of the suite of CDR possibilities. The options include strategies grounded in improved ecosystem stewardship (e.g., reforestation and afforestation, conservation agriculture); strategies that are also biomass-based but with more engineering and more trade-offs (e.g., biochar additions to soils, bioenergy with carbon capture and storage); and engineered, nonbiological approaches (e.g., enhanced weathering, direct air capture). Second, the presentation will evaluate constraints surrounding CDR deployment at large scale and in peak-and-decline scenarios. These constraints involve, for example, unprecedented rates of land transformation in climate change mitigation pathways limiting warming to 2°C with high probability. They also entail the substantial, little studied risks of scenarios with temperatures peaking and then declining. Third, the presentation will review emerging lessons from CDR implementation to date, such as in legally enforceable forest-offset projects, along with near-term opportunities for catalyzing CDR, such as through low-cost opportunities for

Transportation plays a significant role in carbondioxide (CO2) emissions, accounting for approximately a third of the U.S. inventory. To reduce CO2 emissions in the future, transportation policy makers are planning on making vehicles more efficient and increasing the use of carbon-neutral alternative fuels. In addition, CO2 emissions can be lowered by improving traffic operations, specifically through the reduction of traffic congestion. Traffic congestion and its impact on CO2 emissions wer...

The main problem in calculating the consequences of a carbondioxide dispersion following an accidental release is the formation of solid CO2 during the expansion to ambient pressure. The dispersion models more frequently used in the framework of quantitative risk analysis, cannot describe the

This paper discusses the design and performance of fiber optic distributed intrinsic sensors for dissolved carbondioxide, based on the use optical fibers fabricated so that their entire lengths are chemically sensitive. These fibers use a polymer-clad, silica-core structure where the cladding undergoes a large, reversible, change in optical absorbance in the presence of CO2. The local "cladding loss" induced by this change is thus a direct indication of the carbondioxide concentration in any section of the fiber. To create these fibers, have developed a carbondioxide-permeable polymer material that adheres well to glass, is physically robust, has a refractive index lower than fused silica, and acts as excellent hosts for a unique colorimetric indicator system that respond to CO2. We have used this proprietary material to produce carbon-dioxide sensitive fibers up to 50 meters long, using commercial optical fiber fabrication techniques. The sensors have shown a measurement range of dissolved CO2 of 0 to 1,450 mg/l (0 to 100% CO2 saturation), limit of detection of 0.3 mg/l and precision of 1.0 mg/l in the 0 to 50 mg/l dissolved CO2 range, when a 5 meter-long sensor fiber segment is used. Maximum fiber length, minimum detectable concentration, and spatial resolution can be adjusted by adjusting indicator concentration and fiber design.

An increase in carbondioxide (CO2) concentrations in the atmosphere due to anthropogenic activities is responsible for global warming and hence in recent years, CO2 measurement network has expanded globally. In the monsoon season (July–September) of year 2011, we carried out measurements of CO2 and water ...

Background: We tested the hypothesis that classroom carbondioxide (CO[subscript 2]) concentration is inversely related to child school attendance and educational attainment. Methods: Concentrations of CO[subscript 2] were measured over a 3-5?day period in 60 naturally ventilated classrooms of primary school children in Scotland. Concentrations of…

Carbondioxide exhaled by people can be used as a tracer gas for air change measurements in homes. Good mixing of tracer gas with room air is a necessary condition to obtain accurate results. However, the use of fans to ensure mixing is inconvenient. The natural room distribution of metabolic CO2...

Vapor-liquid equilibrium (VLE) data were predicted for the binary mixture of carbondioxide (CO2) and dimethyl ether (DME) at ten temperatures ranging from 273.15 to 386.56 K and pressure upto 7.9 MPa to observe this mixture's potential of COP enhancement and capacity modulation as a working fluid in a refrigeration ...

A pedagogical experiment is described to examine the physical absorption of gases, in this case carbondioxide, in a hollow fiber membrane contactor (HFMC) where the absorption concentration profile can be followed by a color change. The HFMC is used to teach important concepts and can be used in interesting applications for students, such as…

In the present work the absorption of carbondioxide into aqueous ammonia solutions has been studied in a stirred cell reactor, at low temperatures and ammonia concentrations ranging from 0.1 to about 7Â kmolÂ m-3. The absorption experiments were carried out at conditions where the so-called pseudo

Flaring been a source of anthropogenic carbondioxide, is a concern to skeptics and local oil producing communities as a significant contributor to global warming, environmental degradation, health risk and economic loss. The purpose of the study was to ascertain the impacts of gas flaring on global warming and the local ...

In this paper, we analyze differences in per capita carbondioxide emissions from 1996 to 2010 in six sectors across 28 provinces in China and examine the σ-convergence, stochastic convergence and β-convergence of these emissions. We also investigate the factors that impact the convergence of per capita carbondioxide emissions in each sector. The results show that per capita carbondioxide emissions in all sectors converged across provinces from 1996 to 2010. Factors that impact the convergence of per capita carbondioxide emissions in each sector vary: GDP (gross domestic product) per capita, industrialization process and population density impact convergence in the Industry sector, while GDP per capita and population density impact convergence in the Transportation, Storage, Postal, and Telecommunications Services sector. Aside from GDP per capita and population density, trade openness also impacts convergence in the Wholesale, Retail, Trade, and Catering Service sector. Population density is the only factor that impacts convergence in the Residential Consumption sector. - Highlights: • Analyze differences in CO 2 emissions in six sectors among 28 provinces in China. • Examine the convergence of CO 2 emissions in six sectors. • Investigate factors impact on convergence of CO 2 emissions in each sector. • Factors impact on convergence of per capita CO 2 emissions in each sector vary

Sustainable development and climate change is considered to be one of the top challenges of humanity. Electrochemical carbondioxide (CO2) reduction to fuels or fuel precursor using renewable electricity is a very promising way to recycle CO2 and store the electricity. This would also provide

An input-output framework is adopted to estimate China's carbondioxide (CO2) emissions as generated by its exports in 2002. More than one half of China's exports are related to international production fragmentation. These processing exports generate relatively little value added but also

risks of climate change. Meeting global energy demand whilst limiting or reducing carbondioxide emissions presents an enormous challenge. Energy outlooks show that between now and 2030 the bulk of the increase in energy demand will be met by fossil fuels (IPCC,. 2001). Renewable energy sources, such as wind and.

This manuscript describes an exploratory study on the synthesis of fatty acid/potato starch esters using supercritical carbondioxide (scCO(2)) as the solvent. The effects of process variables such as pressure (6-25 MPa), temperature (120-150 degrees C) and various basic catalysts and fatty acid

Measurement of nitric oxide levels in exhaled ah-is commonly performed using a chemiluminescence detector. However, water vapour and carbondioxide affect the chemiluminescence process, The influence of these gases at the concentrations present in exhaled air has not vet been studied. For this in

In the present work, new experimental data are presented on the solubility of carbondioxide in aqueous piperazine solutions, for concentrations of 0.2 and 0.6 molar piperazine and temperatures of 25, 40, and 70Â°C respectively. The present data, and other data available in the literature, were

Except temperature of solvent, all study variables showed strong relation with the amount of carbondioxide absorbed (with a P-value < 0.05). Uniquely, this study has evaluated the potential for sodium bicarbonate production from the CO2 absorbed using gravimetric analysis. It is also possible to recover over 28% crystal ...

Background: Acid base alterations occur during laparoscopy with carbondioxide insufflation. The purpose of this study was to investigate the effects of low tidal volume ventilation on acid base status during pneumoperitonium. Materials and Methods: 30 patients undergoing laparoscopic surgery under General Anaesthesia ...

To understand the factors controlling carbondioxide (CO sub(2)) exchanges near land-sea boundary diurnal observations have been made twice on CO sub(2) in the air and water in a coastal region. The results suggest that CO sub(2) enrichment...

... are very important to CO2 bio-fixation and carbohydrate accumulation in microalgae. The objective of this study was to optimize semi-continuous culture conditions of Tetraselmis subcordiformis in a rectangular airlift photobioreactor for obtaining maximized carbondioxide fixation rate and intracellular starch productivity.

The loss of carbondioxide (CO2) to the environmentduring microalgae cultivation is undesirable for both environmentaland economic reasons. In this study, a phototrophic biofilm growthmodel was developed and validated with the objective to maximizeboth CO2 utilization efficiency

textabstractIntravenous carbondioxide (CO2) was employed to cause echocardiographic contrast in 40 patients. One to 3 cc of medically pure CO2 were agitated with 5 to 8 cc of 5% dextrose in water and rapidly injected into an upper extremity vein. Contrast was obtained in all patients. In 33

Full Text Available It is presented the calculus of the two-phase ejector for carbondioxide heat pump. The method of calculus is based on the method elaborated by S.M. Kandil, W.E. Lear, S.A. Sherif, and is modified taking into account entrainment ratio as the input for the calculus.

Carbondioxide (CO2) exchange between the atmosphere and the Wadden Sea, a shallow coastal region along the northern Netherlands, has been measured from April 2006 onwards on a tidal flat and over open water. Tidal flat measurements were done using a flux chamber, and ship borne measurements using

An increase in carbondioxide (CO2) concentrations in the atmosphere due to anthropogenic activities is responsible for global warming and hence in recent .... The vehicular traffic was low with about 10 vehicles passing in one hour. The ... Towards west and north, at a distance of about 100 m, thorny plants with a height of.

Mission Pilot Ken Bowersox, busy at work on the wiring harness for the Regenerative CarbonDioxide Removal System located under the mid deck floor. Photo shows Bowersox splicing wires together to 'fool' a faulty sensor that caused the 'air conditioner' to shut down.

Dry-cleaning is a process for removing soils and stains from fabrics and garments which uses a non-aqueous solvent with detergent added. The currently most used dry-cleaning solvent is perchloroethylene (PER), which is toxic, environmentally harmful and suspected to be carcinogenic. Carbondioxide

The removal of carbondioxide from process gas streams is an important step in many industrial processes for a number of technical, economical or environmental reasons. The conventional technology to capture CO2 on large scale is the absorption - desorption process, in which (aqueous) solutions of

Carbondioxide and water vapour in the atmo- sphere are considered as the green-house gases and responsible for the global warming, hence much attention has been given to its measurement and analysis (Jones et al. 1978; Jones and Smith 1977;. Leuning et al. 1982; Ohtaki and Matsui 1982;. Ohtaki 1985).

Global warming and other environmental concerns are fueling increased focus on sustainability resulting in new and stringent guidelines, especially with regard to emissions [1]. Greenhouse gases are prevalent and among harmful emissions that are targeted to be reduced; carbondioxide (CO2...... of feedstock [4], in this case carbondioxide. This stage contains three steps, each incorporating relevant methods and tools. First, with the help of user specifications, the problem is specified. Then, the processing routes linking feed and product are represented via a superstructure. This is performed....... This database contains information on the raw material (including different carbondioxide emission conditions), the products and the reactions linking these. With this help of the database it is possible to quickly compare utilization processes for a specific problem as the information is easily accessible...

The interaction of carbondioxide and erbium thin films is characterized at 300 to 900 0 C and 5 x 10 -7 torr. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C, preceded by desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface. The sticking coefficients were plotted as a function of Langmuirs of carbondioxide exposure. Between 400 and 600 0 C, the length of the exposure was found to be more important than the temperature of the exposure in determining the sticking coefficient. Some evolution of carbon monoxide was noted particularly in the 400 to 500 0 C region. An 80% conversion of carbondioxide to carbon monoxide was measured at 500 0 C. The film pumping speeds were compared with published vapor pressure data for erbium. This comparison indicated that a significant portion of the pumping action observed at temperatures of 800 0 C and above was due to evaporation of erbium metal

Four State of the Art (SOA) reports, ''Atmospheric CarbonDioxide and the Global Carbon Cycle,'' ''Direct Effects of Increasing CarbonDioxide on Vegetation,'' ''Detecting the Climatic Effects of Increasing CarbonDioxide,'' and ''Projecting the Climatic Effects of Increasing CarbonDioxide,'' and two companion reports, ''Characterization of Information Requirements for Studies of CO/sub 2/ Effects: Water Resources, Agriculture, Fisheries, Forests and Human Health'' and ''Glaciers, Ice Sheets, and Sea Level: Effect of a CO/sub 2/-Induced Climatic Change,'' were published by the US Department of Energy's CarbonDioxide Research Division. Considerable information on atmospheric carbondioxide and its possible effects on world climate is summarized in these six volumes. Each volume has its own index, but to make the information that is distributed throughout the six volumes more accessible and usable, comprehensive citation and subject indexes have been compiled. The subject indexes of the individual volumes have been edited to provide a uniformity from volume to volume and also to draw distinctions not needed in the separate volumes' indexes. Also, the comprehensive subject index has been formatted in a matrix arrangement to graphically show the distribution of subject treatment from volume to volume. Other aids include cross references between the scientific and common names of the animals and plants referred to, a glossary of special terms used, tables of data and conversion factors related to the data, and explanations of the acronyms and initialisms used in the texts of the six volumes. The executive summaries of the six volumes are collected and reproduced to allow the readers interested in the contents of one volume to rapidly gain information on the contents of the other volumes.

To assess the accuracy of measurements of end tidal carbondioxide (CO2) during neonatal transport compared with arterial and transcutaneous measurements. Paired end tidal and transcutaneous CO2 recordings were taken frequently during road transport of 21 ventilated neonates. The first paired CO2 values were compared with an arterial blood gas. The differences between arterial CO2 (Paco2), transcutaneous CO2 (TcPco2), and end tidal CO2 (Petco2) were analysed. The Bland-Altman method was used to assess bias and repeatability. Petco2 correlated strongly with Paco2 and TcPco2. However, Petco2 underestimated Paco2 at a clinically unacceptable level (mean (SD) 1.1 (0.70) kPa) and did not trend reliably over time within individual subjects. The Petco2 bias was independent of Paco2 and severity of lung disease. Petco2 had an unacceptable under-recording bias. TcPco2 should currently be considered the preferred method of non-invasive CO2 monitoring for neonatal transport.

This paper records the effects of carbondioxide when used for euthanasia, on behaviour, electrical brain activity and heart rate in rats. Four different methods were used. Animals were placed in a box (a) that was completely filled with carbondioxide; (b) into which carbondioxide was streamed at

extracted from the acidified seawater. Optionally, the ion exchange reaction can be conducted under conditions which produce hydrogen as well as carbondioxide . The carbondioxide and hydrogen may be used to produce hydrocarbons....acidification of seawater by subjecting the seawater to an ion exchange reaction to exchange H.sup. ions for Na.sup. ions. Carbondioxide may be

Carbondioxide capture and separation are important industrial processes that allow the use of carbondioxide for the production of a range of chemical products and materials, and to minimize the effects of carbondioxide emission. Porous metal-organic frameworks are promising materials to achieve

In laboratory experiments, toxicity of carbondioxide and carbondioxide - phosphine mixture was investigated against 4 species of stored-product insects. In empty-space trials, estimates of the median lethal doses of carbondioxide against adults of Oryzaephilus surinamensis (L.), Lasioderma serricorne (F.) and eggs of ...

A carbondioxide absorbent composition is described, including (i) a liquid, nonaqueous silicon-based material, functionalized with one or more groups that either reversibly react with CO.sub.2 or have a high-affinity for CO.sub.2; and (ii) a hydroxy-containing solvent that is capable of dissolving both the silicon-based material and a reaction product of the silicon-based material and CO.sub.2. The absorbent may be utilized in methods to reduce carbondioxide in an exhaust gas, and finds particular utility in power plants.

This article discusses public acceptance of carbon capture and storage (CCS). Responses by citizens are described in relation to responses by professionally involved actors. Interviews with members of the government, industry and environmental NGOs showed that these professional actors are interested in starting up storage projects, based on thorough evaluation processes, including discussions on multi-actor working groups. As appeared from a survey among citizens living near a potential storage site (N=103), public attitudes in general were slightly positive, but attitudes towards storage nearby were slightly negative. The general public appeared to have little knowledge about CO 2 -storage, and have little desire for more information. Under these circumstances, trust in the professional actors is particularly important. NGOs were found to be trusted most, and industry least by the general public. Trust in each of the three actors appeared to depend on perceived competence and intentions, which in turn were found to be related to perceived similarity of goals and thinking between trustee and trustor. Implications for communication about CCS are discussed. (author)

Regenerable sorbents based on sodium carbonate (Na{sub 2}CO{sub 3}) can be used to separate carbondioxide (CO{sub 2}) from coal-fired power plant flue gas. Upon thermal regeneration and condensation of water vapor, CO{sub 2} is released in a concentrated form that is suitable for reuse or sequestration. During the research project described in this report, the technical feasibility and economic viability of a thermal-swing CO{sub 2} separation process based on dry, regenerable, carbonate sorbents was confirmed. This process was designated as RTI's Dry Carbonate Process. RTI tested the Dry Carbonate Process through various research phases including thermogravimetric analysis (TGA); bench-scale fixed-bed, bench-scale fluidized-bed, bench-scale co-current downflow reactor testing; pilot-scale entrained-bed testing; and bench-scale demonstration testing with actual coal-fired flue gas. All phases of testing showed the feasibility of the process to capture greater than 90% of the CO{sub 2} present in coal-fired flue gas. Attrition-resistant sorbents were developed, and these sorbents were found to retain their CO{sub 2} removal activity through multiple cycles of adsorption and regeneration. The sodium carbonate-based sorbents developed by RTI react with CO{sub 2} and water vapor at temperatures below 80 C to form sodium bicarbonate (NaHCO3) and/or Wegscheider's salt. This reaction is reversed at temperatures greater than 120 C to release an equimolar mixture of CO{sub 2} and water vapor. After condensation of the water, a pure CO{sub 2} stream can be obtained. TGA testing showed that the Na{sub 2}CO3 sorbents react irreversibly with sulfur dioxide (SO{sub 2}) and hydrogen chloride (HCl) (at the operating conditions for this process). Trace levels of these contaminants are expected to be present in desulfurized flue gas. The sorbents did not collect detectable quantities of mercury (Hg). A process was designed for the Na{sub 2}CO{sub 3}-based sorbent that

Full Text Available To investigate green house gas emissions from compost preparations, methane and carbondioxide concentrations and emission rates at different accumulative times and composting periods were determined. While the accumulative time was less than 10 min with a closed acrylic chamber, meth ane and carbondioxide emissions in creased slightly but with high fluntuation in the sampling e ror, and these values decreased significantly when the accumulative time was more than 20 min. During the 8 weeks of composting, the methane emission rate reaches its peak near the end of the second week and the carbondioxide emission rate does the same near the end of third week. Meth ane and carbondioxide emissions had high val ues at the first stage of com post ing and then de creased grad u ally for the ma tu rity of com post. Carbondioxide emission (y was significantly related to temperature (x1, moisture content (x2, and total or ganiccarbon (x3; and there gression equation is: y = 3.11907x1 + 6.19236x2 - 6.63081x3 - 50.62498. The re gres sion equa tion be tween meth ane emis sion (y? and mois ture con tent (x2, pH (x4, C/N ra tio (x5, and ash con tent (x6 is: y?= 0.13225x2 - 0.97046x4 - 1.10599x5 - 0.55220x6 + 50.77057 in the ini tial com post ing stage (weeks 1 to 3; while, the equa tion is: y?= 0.02824x2 - 0.0037x4 - 0.1499x5 - 0.07013x6 + 4.13589 in the later compost ing stage (weeks 4 to 8. Dif ferent stage composts have significant variation of properties and greenhouse gas emissions. Moreover, the emissions may be reduced by manipulating the proper factors.

Full Text Available The catalytic synthesis of cyclic carbonates using carbondioxide as a C1-building block is a highly active area of research. Here, we review the catalytic production of enantiomerically enriched cyclic carbonates via kinetic resolution of racemic epoxides catalysed by metal-containing catalyst systems.

Great quantities of hydrocarbon fuels will be needed for the foreseeable future, even if electricity based energy carriers begin to partially replace liquid hydrocarbons in the transportation sector. Fossil fuels and biomass are the most common feedstocks for production of hydrocarbon fuels. However, using renewable or nuclear energy, carbondioxide and water can be recycled into sustainable hydrocarbon fuels in non-biological processes which remove oxygen from CO2 and H2O (the reverse of fuel combustion). Capture of CO2 from the atmosphere would enable a closed-loop carbon-neutral fuel cycle. The purpose of this work was to develop critical components of a system that recycles CO2 into liquid hydrocarbon fuels. The concept is examined at several scales, beginning with a broad scope analysis of large-scale sustainable energy systems and ultimately studying electrolysis of CO 2 and H2O in high temperature solid oxide cells as the heart of the energy conversion, in the form of three experimental studies. The contributions of these studies include discoveries about electrochemistry and materials that could significantly improve the overall energy use and economics of the CO2-to-fuels system. The broad scale study begins by assessing the sustainability and practicality of the various energy carriers that could replace petroleum-derived hydrocarbon fuels, including other hydrocarbons, hydrogen, and storage of electricity on-board vehicles in batteries, ultracapacitors, and flywheels. Any energy carrier can store the energy of any energy source. This sets the context for CO2 recycling -- sustainable energy sources like solar and wind power can be used to provide the most energy-dense, convenient fuels which can be readily used in the existing infrastructure. The many ways to recycle CO2 into hydrocarbons, based on thermolysis, thermochemical loops, electrolysis, and photoelectrolysis of CO2 and/or H 2O, are critically reviewed. A process based on high temperature co

CCS research has been focused on CO2 storage in geologic formations, with many potential risks. An alternative to conventional geologic storage is carbon mineralization, where CO2 is reacted with metal cations to form carbonate minerals. Mineralization methods can be broadly divided into two categories: in situ and ex situ. In situ mineralization, or mineral trapping, is a component of underground geologic sequestration, in which a portion of the injected CO2 reacts with alkaline rock present in the target formation to form solid carbonate species. In ex situ mineralization, the carbonation reaction occurs above ground, within a separate reactor or industrial process. This literature review is meant to provide an update on the current status of research on CO2 mineralization. 2

Chemoselective hydrogenation of halogenated nitrobenzenes over Pt/C catalysts proceeds effectively in supercritical carbondioxide (scCO2) to produce halogenated anilines with excellent selectivity; the rate of the hydrogenation of nitro groups is markedly enhanced in scCO2 compared to the neat reaction, and the dehalogenation reaction is significantly suppressed.

Information about the past and present concentrations of CO 2 in the atmosphere and variations in climate can be obtained from measurements of stable isotopes in tree rings; specifically carbon-13, oxygen-18 and deuterium. The analysis of these stable isotopes in tree rings is a relatively new and rapidly developing field. This proceedings volume contains most of the papers presented at the meeting. The first paper gives an overview of the status of carbon-13 research. Papers relating to carbon-13 are in section I and grouped separately from the contributions on carbon-14. Although the meeting was primarily concerned with stable isotopes, all carbon isotopic analysis may be helpful in understanding the carbon-13 record in tree rings. The papers on hydrogen and oxygen isotope studies are in sections II and III respectively. The remaining sections contain papers that consider more than one isotope at a time, general topics related to isotopes, atmospheric changes and tree growth, and methods of isotopic analysis

Carbon sequestration may be the solution to face our difficulty to cut down the use of fossil energies. CO 2 has to be separated from other gases released by thermal power plants before being stored in deep geological layers, there it can stay as a gas, or it can be dissolved in a fluid phase, or it can react with minerals and be integrated to a solid phase. Oil fields and deep saline water reservoirs are natural candidates for carbon sequestration. Carbon sequestration implies the installation of a network of pipelines to transport CO 2 from the place of production to the place of sequestration. The high cost of carbon sequestration implies the implementation of financial incentives from governments. Some economists foresee a raise of the electricity cost up to 50% if carbon sequestration is used. Other economists see a contradiction: sequestration techniques will not be available in a short term range while numerous thermal power plants are planned to be built in the decade. So carbon sequestration may arrive too late and at a cost that may be not competitive with some renewable energies like off-shore wind energy or thermal solar energy which will be full-grown at that time. (A.C.)

The fugitive carbon is the difference between the 7 billion or so tons that spew as carbondioxide from smokestacks and burning tropical forests and the 3.4 billion tons known to stay in the atmosphere. Finding the other 3 billion or 4 billion tons has frustrated researchers for the past 15 years. The oceans certainly take up some of it. Any forecast of global warming has to be based on how much of the carbondioxide released by human activity will remain in the atmosphere, and predictions vary by 30% depending on the mix of oceanic and terrestrial processes assumed to be removing the gas. What's more, those predictions assume that the processes at work today will go on operating. But not knowing where all the carbon is going raises the unnerving possibility that whatever processes are removing it may soon fall down on the job without warning, accelerating any warming. Such concerns add urgency to the question of whether the ocean harbors the missing carbon. But there's no simple way to find out. The obvious strategy might seem to be to measure the carbon content of the ocean repeatedly to see how much it increases year by year. The trouble is that several billion tons of added carbon, though impressive on a human scale, are undetectable against the huge swings in ocean carbon that occur from season to season, year to year, and place to place

Full Text Available Though carbondioxide is the main green house gas due to burning of fossil resource or miscellaneous chemical processes, we propose here that carbondioxide be a new material for energy storage. Since it can be the key to find the solution for three critical issues facing the world: food ecosystems, the greenhouse issue and energy storage. We propose to identify the carbon recovery through a circular industrial revolution in the first part, and in the second part we present the starting way of three business plants to do that from industrial examples. By pointing out all the economic constraints and the hidden competitions between energy, water and food, we try to qualify the phrase “sustainable development” and open the way of a huge circular economy.

Carbondioxide gas as a working gas produces a stable plasma-torch by making use of 2.45 GHz microwaves. The temperature of the torch flame is measured by making use of optical spectroscopy and a thermocouple device. Two distinctive regions are exhibited, a bright, whitish region of a high-temperature zone and a bluish, dimmer region of a relatively low-temperature zone. The bright, whitish region is a typical torch based on plasma species where an analytical investigation indicates dissociation of a substantial fraction of carbondioxide molecules, forming carbon monoxides and oxygen atoms. The emission profiles of the oxygen atoms and the carbon monoxide molecules confirm the theoretical predictions of carbondioxide disintegration in the torch. Various hydrocarbon materials may be introduced into the carbondioxide torch, regenerating new resources and reducing carbondioxide concentration in the torch. As an example, coal powders in the carbondioxide torch are converted into carbon monoxide according to the reaction of CO 2 + C → 2CO, reducing a substantial amount of carbondioxide concentration in the torch. In this regards, the microwave plasma torch may be one of the best ways of converting the carbondioxides into useful new materials. - Highlights: • Carbondioxide gas produces a plasma-torch by making use of 2.45 GHz microwaves. • The temperature measurement of torch flame by optical spectroscopy. • Disintegration of carbondioxide into carbon monoxide and oxygen atom. • Emission profiles of carbon monoxide confirm disintegration theory. • Conversion of carbondioxide into carbon monoxide in the plasma torch. - This article presents carbon-dioxide plasma torch operated by microwaves and its applications to regeneration of new resources, eliminating carbondioxide molecules.

Misconceptions of siphon action include assumptions that intermolecular attractions play a key role and that siphons will operate in a vacuum. These are belied by the siphoning of gaseous carbondioxide and behaviour of siphons under reduced pressure. These procedures are suitable for classroom demonstrations. The principles of siphon action are…

[1] Disturbances are important for renewal of North American forests. Here we summarize more than 180 site years of eddy covariance measurements of carbondioxide flux made at forest chronosequences in North America. The disturbances included standreplacing fire (Alaska, Arizona, Manitoba, and Saskatchewan) and harvest (British Columbia, Florida, New Brunswick, Oregon...

The possibilities for reducing carbondioxide emissions from the pulp and paper industry by calcium carbonation are presented. The current precipitated calcium carbonate (PCC) production uses mined, crushed calcium carbonate as raw materials. If calcium silicates were used instead, carbondioxide emissions from the calcination of carbonates would be eliminated. In Finland, there could, thus, be a potential for eliminating 200 kt of carbondioxide emissions per year, considering only the PCC used in the pulp and paper industry. A preliminary investigation of the feasibility to produce PCC from calcium silicates and the potential to replace calcium carbonate as the raw material was made. Calcium carbonate can be manufactured from calcium silicates by various methods, but only a few have been experimentally verified. The possibility and feasibility of these methods as a replacement for the current PCC production process was studied by thermodynamic equilibrium calculations using HSC software and process modelling using Aspen Plus[reg]. The results from the process modelling showed that a process that uses acetic acid for extraction of the calcium ions is a high potential option for sequestering carbondioxide by mineral carbonation. The main obstacle seems to be the limited availability and relatively high price of wollastonite, which is a mineral with high calcium silicate content. An alternative is to use the more common, but also more complex, basalt rock instead

Full Text Available This paper reviews the application of carbonation technology to the environmental industry as a way of reducing carbondioxide (CO2, a green house gas, including the presentation of related projects of our research group. An alternative technology to very slow natural carbonation is the co-called ‘accelerated carbonation’, which completes its fast reaction within few hours by using pure CO2. Carbonation technology is widely applied to solidify or stabilize solid combustion residues from municipal solid wastes, paper mill wastes, etc. and contaminated soils, and to manufacture precipitated calcium carbonate (PCC. Carbonated products can be utilized as aggregates in the concrete industry and as alkaline fillers in the paper (or recycled paper making industry. The quantity of captured CO2 in carbonated products can be evaluated by measuring mass loss of heated samples by thermo-gravimetric (TG analysis. The industrial carbonation technology could contribute to both reduction of CO2 emissions and environmental remediation.

Full Text Available We report on the direct conversion of carbondioxide (CO2 in a photoelectrochemical cell consisting of germanium doped gallium nitride nanowire anode and copper (Cu cathode. Various products including methane (CH4, carbon monoxide (CO, and formic acid (HCOOH were observed under light illumination. A Faradaic efficiency of ∼10% was measured for HCOOH. Furthermore, this photoelectrochemical system showed enhanced stability for 6 h CO2 reduction reaction on low cost, large area Si substrates.

A new model has been constructed for calculating the level of atmospheric CO(2) during the past 570 million years. A series of successive steady states for CO(2) is used in order to calculate CO(2) level from a feedback function for the weathering of silicate minerals. Processes considered are: sedimentary burial of organic matter and carbonates; continental weathering of silicates, carbonates, and organic matter; and volcanic and metamorphic degassing of CO(2). Sediment burial rates are calculated with the use of an isotope mass-balance model and carbon isotopic data on ancient seawater. Weathering rates are calculated from estimates of past changes in continental land area, mean elevation, and river runoff combined with estimates of the effects of the evolution of vascular land plants. Past degassing rates are estimated from changes in the rate of generation of sea floor and the shift of carbonate deposition from platforms to the deep sea. The model results indicate that CO(2) levels were high during the Mesozoic and early Paleozoic and low during the Permo-Carboniferous and late Cenozoic. These results correspond to independently deduced Phanerozoic paleoclimates and support the notion that the atmospheric CO(2) greenhouse mechanism is a major control on climate over very long time scales.

The aim of enhanced weathering is to capture CO2 by the carbonation of silicates, or by dissolution of these silicates during which the greenhouse gas CO2 is converted to bicarbonate in solution. Research in this field is still focused on increasing the rate of reaction, but the required

Full Text Available Control over the CO2 emission via automobiles and industrial exhaust in atmosphere, is one of the major concerns to render environmental friendly milieu. Adsorption can be considered to be one of the more promising methods, offering potential energy savings compared to absorbent systems. Different carbon nanostructures (activated carbon and carbon nanotubes have attracted attention as CO2 adsorbents due to their unique surface morphology. In the present work, we have demonstrated the CO2 adsorption capacity of graphene, prepared via hydrogen induced exfoliation of graphitic oxide at moderate temperatures. The CO2 adsorption study was performed using high pressure Sieverts apparatus and capacity was calculated by gas equation using van der Waals corrections. Physical adsorption of CO2 molecules in graphene was confirmed by FTIR study. Synthesis of graphene sheets via hydrogen exfoliation is possible at large scale and lower cost and higher adsorption capacity of as prepared graphene compared to other carbon nanostructures suggests its possible use as CO2 adsorbent for industrial application. Maximum adsorption capacity of 21.6 mmole/g was observed at 11 bar pressure and room temperature (25 ºC.

The invention provides systems and methods for generating organic compounds using carbondioxide as a source of carbon and electrical current as an energy source. In one embodiment, a reaction cell is provided having a cathode electrode and an anode electrode that are connected to a source of electrical power, and which are separated by a permeable membrane. A biological film is provided on the cathode. The biological film comprises a bacterium that can accept electrons and that can convert carbondioxide to a carbon-bearing compound and water in a cathode half-reaction. At the anode, water is decomposed to free molecular oxygen and solvated protons in an anode half-reaction. The half-reactions are driven by the application of electrical current from an external source. Compounds that have been produced include acetate, butanol, 2-oxobutyrate, propanol, ethanol, and formate.

The invention provides systems and methods for generating organic compounds using carbondioxide as a source of carbon and electrical current as an energy source. In one embodiment, a reaction cell is provided having a cathode electrode and an anode electrode that are connected to a source of electrical power, and which are separated by a permeable membrane. A biological film is provided on the cathode. The biological film comprises a bacterium that can accept electrons and that can convert carbondioxide to a carbon-bearing compound and water in a cathode half-reaction. At the anode, water is decomposed to free molecular oxygen and solvated protons in an anode half-reaction. The half-reactions are driven by the application of electrical current from an external source. Compounds that have been produced include acetate, butanol, 2-oxobutyrate, propanol, ethanol, and formate.

The present study aimed at investigating the carbon metabolism in terms of carbondioxide fixation and its destination in microalgae cultivations. To this purpose, analysis of growth parameters, media of cultivation, biomass composition and productivity and nutrients balance were performed. Four microalgae suitable for mass cultivation were evaluated: Dunaliella tertiolecta SAD-13.86, Chlorella vulgaris LEB-104, Spirulina platensis LEB-52 and Botryococcus braunii SAG-30.81. Global rates of carbondioxide and oxygen were determinated by a system developed in our laboratory. B. braunii presented the highest CO(2) fixation rate, followed by S. platensis,D. tertiolecta and C. vulgaris (496.98, 318.61, 272.4 and 251.64 mg L(-1)day(-1), respectively). Carbondioxide fixated was mainly used for microalgal biomass production. Nitrogen, phosphorus (calcium for D. tertiolecta), potassium and magnesium consumption rates (mg gX(-1)) were evaluated for the four microalgae. Biomass composition presented a predominance of proteins but also a high amount of lipids, especially in D. tertiolecta and B. braunii. (c) 2010. Published by Elsevier Ltd.

Carbondioxide (CO{sub 2}) has been detected on the surface of several icy moons of Jupiter and Saturn via observation of the ν{sub 3} band with the Near-Infrared Mapping Spectrometer on board the Galileo spacecraft and the Visible-Infrared Mapping Spectrometer on board the Cassini spacecraft. Interestingly, the CO{sub 2} band for several of these moons exhibits a blueshift along with a broader profile than that seen in laboratory studies and other astrophysical environments. As such, numerous attempts have been made in order to clarify this abnormal behavior; however, it currently lacks an acceptable physical or chemical explanation. We present a rather surprising result pertaining to the synthesis of carbondioxide in a polar environment. Here, carbonic acid was synthesized in a water (H{sub 2}O)-carbondioxide (CO{sub 2}) (1:5) ice mixture exposed to ionizing radiation in the form of 5 keV electrons. The irradiated ice mixture was then annealed, producing pure carbonic acid which was then subsequently irradiated, recycling water and carbondioxide. However, the observed carbondioxide ν{sub 3} band matches almost exactly with that observed on Callisto; subsequent temperature program desorption studies reveal that carbondioxide synthesized under these conditions remains in solid form until 160 K, i.e., the sublimation temperature of water. Consequently, our results suggest that carbondioxide on Callisto as well as other icy moons is indeed complexed with water rationalizing the shift in peak frequency, broad profile, and the solid state existence on these relatively warm moons.

Carbondioxide capture and separation are important industrial processes that allow the use of carbondioxide for the production of a range of chemical products and materials, and to minimize the effects of carbondioxide emission. Porous metal-organic frameworks are promising materials to achieve such separations and to replace current technologies, which use aqueous solvents to chemically absorb carbondioxide. Here we show that a metal-organic frameworks (UTSA-16) displays high uptake (160 cm(3) cm(-3)) of CO(2) at ambient conditions, making it a potentially useful adsorbent material for post-combustion carbondioxide capture and biogas stream purification. This has been further confirmed by simulated breakthrough experiments. The high storage capacities and selectivities of UTSA-16 for carbondioxide capture are attributed to the optimal pore cages and the strong binding sites to carbondioxide, which have been demonstrated by neutron diffraction studies.

Using carbondioxide (CO2) as a feedstock for commodity synthesis is an attractive means of reducing greenhouse gas emissions and a possible stepping-stone towards renewable synthetic fuels. A major impediment to synthesizing compounds from CO2 is the difficulty of forming carbon-carbon (C-C) bonds efficiently: although CO2 reacts readily with carbon-centred nucleophiles, generating these intermediates requires high-energy reagents (such as highly reducing metals or strong organic bases), carbon-heteroatom bonds or relatively acidic carbon-hydrogen (C-H) bonds. These requirements negate the environmental benefit of using CO2 as a substrate and limit the chemistry to low-volume targets. Here we show that intermediate-temperature (200 to 350 degrees Celsius) molten salts containing caesium or potassium cations enable carbonate ions (CO3(2-)) to deprotonate very weakly acidic C-H bonds (pKa > 40), generating carbon-centred nucleophiles that react with CO2 to form carboxylates. To illustrate a potential application, we use C-H carboxylation followed by protonation to convert 2-furoic acid into furan-2,5-dicarboxylic acid (FDCA)--a highly desirable bio-based feedstock with numerous applications, including the synthesis of polyethylene furandicarboxylate (PEF), which is a potential large-scale substitute for petroleum-derived polyethylene terephthalate (PET). Since 2-furoic acid can readily be made from lignocellulose, CO3(2-)-promoted C-H carboxylation thus reveals a way to transform inedible biomass and CO2 into a valuable feedstock chemical. Our results provide a new strategy for using CO2 in the synthesis of multi-carbon compounds.

Results are presented on the development of reversible sorbents for the combined carbondioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbondioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Furthermore, the current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is nonregenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for simultaneous carbondioxide, ammonia, formaldehyde, and water sorption. Multiple adsorption/vacuum-regeneration cycles were demonstrated at room temperature, and also the enhancement of formaldehyde sorption by the presence of ammonia in the gas mixture.

The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbondioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO{sub 2} capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO{sub 2} and H{sub 2}O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbondioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed

The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbondioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO(sub 2) capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO(sub 2) and H(sub 2)O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbondioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed-bed, fluidized-bed, and transport

The concomitant recycling of waste and carbondioxide emissions is the subject of developing technology designed to close the industrial process loop and facilitate the bulk-re-use of waste in, for example, construction. The present work discusses a treatment step that employs accelerated carbonation to convert gaseous carbondioxide into solid calcium carbonate through a reaction with industrial thermal residues. Treatment by accelerated carbonation enabled a synthetic aggregate to be made from thermal residues and waste quarry fines. The aggregates produced had a bulk density below 1000 kg/m(3) and a high water absorption capacity. Aggregate crushing strengths were between 30% and 90% stronger than the proprietary lightweight expanded clay aggregate available in the UK. Cast concrete blocks containing the carbonated aggregate achieve compressive strengths of 24 MPa, making them suitable for use with concrete exposed to non-aggressive service environments. The energy intensive firing and sintering processes traditionally required to produce lightweight aggregates can now be augmented by a cold-bonding, low energy method that contributes to the reduction of green house gases to the atmosphere.

A method for the separation of carbondioxide from ambient air and flue gases is provided wherein a phase separating moiety with a second moiety are simultaneously coupled and bonded onto an inert substrate to create a mixture which is subsequently contacted with flue gases or ambient air. The phase-separating moiety is an amine whereas the second moiety is an aminosilane, or a Group 4 propoxide such as titanium (IV) propoxide (tetrapropyl orthotitanate, C.sub.12H.sub.28O.sub.4Ti). The second moiety makes the phase-separating moiety insoluble in the pores of the inert substrate. The new sorbents have a high carbondioxide loading capacity and considerable stability over hundreds of cycles. The synthesis method is readily scalable for commercial and industrial production.

Experimental phase equilibrium data for binary systems involving epsilon-caprolactone, delta-hexalactone, and gamma-caprolactone with carbondioxide have been measured applying the synthetic method using a high-pressure, variable-volume view cell over the temperature range of (303 to 343) K and pressures up to 21 MPa. For the systems investigated, (vapour + liquid) (VLE), (liquid + liquid) (LLE), and (vapour + liquid + liquid) (VLLE) equilibrium were visually recorded. It was observed that an increase in temperature or in carbondioxide concentration led to a pronounced raise in transition pressure values. The experimental results were modelled using the Peng-Robinson equation of state with the conventional quadratic mixing rule, affording a satisfactory representation of the experimental values.

In the framework of the reduction of the carbondioxide emissions in the air, the underground storage of the CO 2 is studied. Some experimentation are already realized in the world and envisaged in France. This document aims to study the juridical aspects of these first works in France. After a presentation of the realization conditions and some recalls on the carbondioxide its capture and storage, the natural CO 2 underground storages and the first artificial storages are discussed. The CO 2 waste qualification, in the framework of the environmental legislation is then detailed with a special task on the Lacq region. The problem of the sea underground storages is also presented. (A.L.B.)

The transient response of a coupled ocean-atmosphere model to an increase of carbondioxide has been the subject of several studies. The models used in these studies explicitly incorporate the effect of heat transport by ocean currents and are different from the model used by Hansen et al. Here the authors evaluate the climatic influence of increasing atmospheric carbondioxide using a coupled model recently developed at the NOAA Geophysical Fluid Dynamics Laboratory. The model response exhibits a marked and unexpected interhemispheric asymmetry. In the circumpolar ocean of the southern hemisphere, a region of deep vertical mixing, the increase of surface air temperature is very slow. In the Northern hemisphere of the model, the rise of surface air temperature is faster and increases with latitude, with the exception of the northern North Atlantic, where it is relatively slow because of the weakening of the thermohaline circulation

This review focuses on the solubility, origin, abundance, and degassing of carbondioxide (CO2) in magma-hydrothermal systems, with applications for those workers interested in intrusion-related deposits of gold and other metals. The solubility of CO2 increases with pressure and magma alkalinity. Its solubility is low relative to that of H2O, so that fluids exsolved deep in the crust tend to have high CO2/H2O compared with fluids evolved closer to the surface. Similarly, CO2/H2O will typically decrease during progressive decompression- or crystallization-induced degassing. The temperature dependence of solubility is a function of the speciation of CO2, which dissolves in molecular form in rhyolites (retrograde temperature solubility), but exists as dissolved carbonate groups in basalts (prograde). Magnesite and dolomite are stable under a relatively wide range of mantle conditions, but melt just above the solidus, thereby contributing CO2 to mantle magmas. Graphite, diamond, and a free CO2-bearing fluid may be the primary carbon-bearing phases in other mantle source regions. Growing evidence suggests that most CO2 is contributed to arc magmas via recycling of subducted oceanic crust and its overlying sediment blanket. Additional carbon can be added to magmas during magma-wallrock interactions in the crust. Studies of fluid and melt inclusions from intrusive and extrusive igneous rocks yield ample evidence that many magmas are vapor saturated as deep as the mid crust (10-15 km) and that CO2 is an appreciable part of the exsolved vapor. Such is the case in both basaltic and some silicic magmas. Under most conditions, the presence of a CO2-bearing vapor does not hinder, and in fact may promote, the ascent and eruption of the host magma. Carbonic fluids are poorly miscible with aqueous fluids, particularly at high temperature and low pressure, so that the presence of CO2 can induce immiscibility both within the magmatic volatile phase and in hydrothermal systems

Chloroplasts isolated from Kalanchoe diagremontiana leaves were capable of photosynthesizing at a rate of 5.4 ..mu..moles of CO/sub 2/ per milligram of chlorophyll per hour. The dark rate of fixation was about 1 percent of the light rate. A high photosynthetic rate was associated with low starch content of the leaves. Ribose 5-phosphate, fructose 1, 6-diphosphate, and dithiothreitol stimulated fixation, whereas phosphoenolpyruvate and azide were inhibitors. The products of CO/sub 2/ fixation were primarily those of the photosynthetic carbon reduction cycle. (auth)

The Calvin cycle of carbondioxide fixation constitutes a biosynthetic pathway for the generation of (multi-carbon) intermediates of central metabolism from the one-carbon compound carbondioxide. The product of this cycle can be used as a precursor for the synthesis of all components of cell

PURPOSE: To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. METHODS: An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbondioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, h...

Full Text Available Indoor environment has huge influence on person’s health and overall comfort. It is of great importance that we realize how essential indoor air quality is, considering we spend on average as much as 90% of our time indoors. There are many factors that affect indoor air quality: specifically, inside air temperature, relative humidity, and odors to name the most important factors. One of the key factors indicating indoor air quality is carbondioxide (CO2 level.

CONCLUSION: Multifunctional fractional carbondioxide laser used in treatment of patients with acne and pigmentation from acne, as well as in the treatment of scars from different backgrounds, is an effective and safe method that causes statistically significant better effect of the treatment, greater patients’ satisfaction, minimal side effects and statistically better response to the therapy, according to assessments by the patient and the therapist.

The construction industry, through its activities and supply chains as well as the operation of the assets that it creates, is a major contributor to global greenhouse gas emissions. Embodied carbondioxide emissions associated with the construction of new assets constitute a growing share of whole-life emissions across all project types and make up nearly a quarter of all annual emissions from the UK built environment. Yet these embodied emissions are still rarely assessed in practice, owing...

The present invention provides titanium dioxide/single-walled carbon nanotube composites (TiO.sub.2/SWCNTs), articles of manufacture, and methods of making and using such composites. In certain embodiments, the present invention provides membrane filters and ceramic articles that are coated with TiO.sub.2/SWCNT composite material. In other embodiments, the present invention provides methods of using TiO.sub.2/SWCNT composite material to purify a sample, such as a water or air sample.

The Remote Operated Vehicle with CarbonDioxide Blasting (ROVCO 2 ), as shown in a front view, is a six-wheeled remote land vehicle used to decontaminate concrete floors. The remote vehicle has a high pressure Cryogenesis blasting subsystem, Oceaneering Technologies (OTECH) developed a CO 2 xY Orthogonal Translational End Effector (COYOTEE) subsystem, and a vacuum/filtration and containment subsystem. Figure 2 shows a block diagram with the various subsystems labeled

Full Text Available In this research the calculations of carbondioxide emissions CO2 in summer May to September 150 day and winter seasons December to February 90 day were performed by using the coefficient of performance for each air and ground source heat pump. The place of study case take relative to solar path in to account and the study case was three halls men women and surgery halls in Al-Musayyib hospital in Babylon.

Lasers for fusion application represent a special class of short-pulse generators; not only must they generate extremely short temporal pulses of high quality, but they must do this at ultra-high powers and satisfy other stringent requirements by this application. This paper presents the status of the research and development of carbon-dioxide laser systems at the Los Alamos Scientific Laboratory, vis-a-vis the fusion requirements

The solar energy is the largest energy source in the world. Using the photosynthesis, we will be able utilise the huge amount of carbondioxide. Microalgae, cyanobacteria, photosynthetic bacteria belong to photosynthetic microorganisms, which assimilate carbondioxide during the photosynthesis. One of the cyanobacteria, Spirulina platensis accumulates carbohydrate photoautotrophically up to 50% of the dry cell weight in the nitrogen-deficient condition. Under an anaerobic condition in the dark, it is degraded into organic compounds such as organic acids, alcohol and sugar. As the hydrogen gas is also evolved in this process, the participation of hydrogenase (Hydrogen producing enzyme) has been suggested in this metabolism. We have investigated several conditions of evolution of hydrogen and production of organic compounds. The bacterial concentration initial pH and temperature had significant effects on hydrogen evolution as well as production of organic compounds. When the bacterial cell concentration was high, the pH of fermentation products was reduced to acidic and the evolution of hydrogen tended to be inhibited. The profiles of fermentation products varied according to the culture condition. The increase of organic acids were remarkable in the inhibitory condition for hydrogen production, such as acidic pH and high temperature. Furthermore these fermentation products were converted into hydrogen gas by using photosynthetic bacterium Rhodobacter sphaeroides RV with light energy. The composition of evolved gas was mainly hydrogen and carbondioxide, and their contents were 78% and 10%, respectively. The total amount of evolved hydrogen was nearly equal to the estimated, value which was calculated by the degradation of each organic acid. Combining this system with the photosynthesis of cyanobacteria, we could accomplish the production of hydrogen by solar energy, carbondioxide and water. And we demonstrated that the evolved gas could be directly supplied to the

Techniques of chlorine and fluorine determination and simultaneous determination of carbon and chlorine in electrolytic uranium dioxide are described. The method of chlorine and fluorine determination is based on their separation during oxide pyrohydrolysis with subsequent spectrophotometric analysis of condensate. Lower determination limits constitute 1 μg for chlorine, 0.5 μg for fluorine. Relative standard deviation when the content of impurities analyzed is 10 -3 % constitutes 0.05-0.07

This study was carried out to investigate the synergistic effects on the CO{sub 2} conversion by the application of semiconductor in the field of gamma-ray. Gamma-ray irradiation was performed to examine the effects of semiconductor application on CO{sub 2} conversion in water and the formation of organic material from carbonate solution. From experimental results it is clear that the supplication of semiconductor in the field of gamma-ray increases the efficiency for CO{sub 2} conversion to organic matter. Based on the obtained experimental results it is obvious that the synergistic effects of semiconductor materials in the gamma-ray field leads to increase of the CO{sub 2} conversion yield to organic matter up to 50 percent compared to the gamma-ray irradiation. The way of achieving higher activity is due to thecatalytic action of semiconductor by gamma-ray irradiation. Zr-doped TiO{sub 2} catalyst prepared by sol-gel method exhibits the higher efficiency for CO{sub 2} conversion in aqueous solution and carbonate containing solution. This effect of Zr-doping can be explained by the formation of additional defects in surface of TiO{sub 2} film. (author)

Highlights: • Evaluation of carbondioxide conversion to methanol by two chemical routes. • HYDROGENATION: conversion via catalytic hydrogenation at high pressure. • BI-REFORMING: conversion via syngas from bi-reforming of natural gas. • HYDROGENATION is viable for hydrogen price inferior to 1000 US$/t. • BI-REFORMING is unable to avoid emissions; viable only if gas price is very low. - Abstract: Chemical conversion of carbondioxide to methanol has the potential to address two relevant sustainability issues: economically feasible replacement of fossil raw materials and avoidance of greenhouse gas emissions. However, chemical stability of carbondioxide is a challenging impediment to conversion requiring severe reaction conditions at the expense of increased energy input, therefore adding capital, operation and environmental costs, which could result in partial or total override of its potential sustainability as feedstock to the chemical and energy industries. This work investigates two innovative chemical destinations of carbondioxide to methanol, namely a direct conversion through carbondioxide hydrogenation (HYDROGENATION), and an indirect via carbondioxide conversion to syngas through bi-reforming (BI-REFORMING). Process simulation is used to obtain mass and energy balances needed to support assessment of economic and environmental performance. A business scenario is considered where an industrial source of nearly pure carbondioxide exists and an investment decision for utilization of carbondioxide is faced. Due to uncertainties in prices of the raw materials, hydrogen (HYDROGENATION) and natural gas (BI-REFORMING), the decision procedure includes the definition of price thresholds to reach profitability. Sensitivity analyses are performed varying costs with greater uncertainty, i.e., carbondioxide and methanol, and recalculating maximum allowable prices of raw materials. The analyses show that in a Brazilian scenario, BI-REFORMING is unlikely

To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbondioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, histopathology features and histomorphometry of collagen. The treated group had a significantly lower weight gain (p=0.038). Histopathology was not significantly different between groups. There was an increase in amount of collagen in 2 cm grafts submitted to carbondioxide therapy (p=0.003). Carboxytherapy didn't influence graft survival rate for 1.5 cm grafts or 2 cm grafts (p=0.567 and p=0.777, respectively). Carbondioxide therapy increased the amount of collagen in 2 cm grafts. CO2 was not significantly different from saline infusion on composite grafts survival, but this study suggests that there is a mechanical effect caused by distension which favored graft survival.

The amount of carbondioxide in atmosphere increase due to deforestation and anthropogenic emissions. The consumption of this gas in vegetal ecosystems must also be considered to know the net mass of CO 2 that gets into the atmosphere. This article summarizes the methodology, results and conclusions of the carbondioxide balance in Spain by autonomous communities. The different fossil fuel consumer sectors (Thermal power plants, industry, transport, domestic and agricultural), forest biomass reduction due to fires and wood extractions for firewood are considered as sources. As sinks, natural and reforested forests, and the equivalent sea are noticed. Basically, the article presents a new methodology to estimate carbondioxide consumption in forest biomass. The average emissions for 1981 to 1990 are presented. A per capita value of 5 t(CO 2 /year is obtained in contrast to the EC average of 8,6 t(CO 2 ) year. The resulting net balance shows that it is only consumed between 20 and 50% of the emitted CO 2 . (Author) 47 refs

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbondioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbondioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbondioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450-600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the "dust bowl" era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4-1.0 m if 21st century CO(2) concentrations exceed 600 ppmv and 0.6-1.9 m for peak CO(2) concentrations exceeding approximately 1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer.

In this work carbondioxide selective membrane materials from a commercially available poly(amide-b-ethylene oxide) (Pebax (R), Arkema) blended with polyethylene glycol ethers are presented. The preferred PEG-ether was PEG-dimethylether (PEG-DME). PEG-DME is well known as a physical solvent for acid gas absorption. It is used under the trade name Genosorb (R) in the Selexol (R) process (UOP) for acid gas removal from natural gas and synthesis gas. The combination of the liquid absorbent with the multiblock copolymer resulted in mechanically stable films with superior CO(2) separation properties. The addition of 50 wt.% PEG-DME to the copolymer resulted in a 8-fold increase of the carbondioxide permeability; the CO(2)/H(2)-selectivity increased simultaneously from 9.1 to 14.9. It is shown that diffusivity as well as solubility of carbondioxide is strongly increased by the blending of the copolymer with PEG-ethers. (c) 2009 Elsevier B.V. All rights reserved.

the ability to liberate CO2 at a later stage in the process, i.e., in a separate compartment. The liberated CO2 presents a carbon neutral way of obtaining pure CO2. The proposed molecular system is based on a small stable organic molecule that potentially have two forms: one without bound CO2 and one......This paper presents an attempt to develop a new system for fixing carbondioxide from the atmosphere. The proposed molecular system has been designed to have the capacity to spontaneously bind CO2 from the atmosphere with high affinity. The molecular system is furthermore designed to have...

Laboratory experiments were performed to study the capacity of CO 2 sequestration and carbon fixation into biomass during the cultivation of the cyanobacteria Aphanothece microscopica Naegeli in refinery wastewater. The influence of the photoperiod (day/night) on the rates of CO 2 sequestration and O 2 release was also determined. Rates of CO 2 sequestration were measured both in the liquid and gaseous phases. The results showed that the capacity of CO 2 sequestration and O 2 release during the day/night experiment was about one-fourth less than that achieved in the continuously illuminated experiment. Equivalence was found between rates of CO 2 sequestration measured in the two phases. Despite large amounts of CO 2 that were sequestered during the cultivation, it is demonstrated that only a small fraction (about 3%) was effectively fixed as microalgae biomass, indicating the existence of other routes of CO 2 conversion in the photobioreactor.

The mechanism of dimethyl carbonate (DMC) synthesis from methanol and carbondioxide over monoclinic zirconia has been investigated using in situ infrared spectroscopy. The dissociative adsorption of methanol occurs more slowly than the adsorption of carbondioxide, but the species formed from methanol are bound more strongly. Upon adsorption, the oxygen atom of methanol binds to coordinately unsaturated Zr4+ cations present at the catalyst surface. Rapid dissociation of the adsorbed methanol leads to the formation of a methoxide group (Zr-OCH3) and the release of a proton, which reacts with a surface hydroxyl group to produce water. Carbondioxide inserts in the Zr-O bond of the methoxide to form a mondentate methyl carbonate group (Zr-OC(O)OCH3). This process is facilitated by the interactions of C and O atoms in CO2 with Lewis acid-base pairs of sites (Zr4+O2-) on the surface of the catalyst. Methyl carbonate species can also be produced via the reaction of methanol with carbondioxide adsorbed in the form of bicarbonate species with methanol, a process that results in the transfer of a methyl group to the carbonate and restores a hydroxyl group to the zirconia surface. The decomposition of DMC on monoclinic zirconia has also been investigated and has been observed to occur via the reverse of the processes described for the synthesis of DMC

Atmospheric carbondioxide is rising and forests and climate is changing exclamation point This combination of fact and premise may be evaluated at a range of temporal and spatial scales with the aid of computer simulators describing the interrelationships between forest vegetation, litter and soil characteristics, and appropriate meteorological variables. Some insights on the effects of climate on the transfers of carbon and the converse effect of carbon transfer on climate are discussed as a basis for assessing the significance of feedbacks between vegetation and climate under conditions of rising atmospheric carbondioxide. Three main classes of forest models are reviewed. These are physiologically-based models, forest succession simulators based on the JABOWA model, and ecosystem-carbon budget models that use compartment transfer rates with empirically estimated coefficients. Some regression modeling approaches are also outlined. Energy budget models applied to forests and grasslands are also reviewed. This review presents examples of forest models; a comprehensive discussion of all available models is not undertaken

Carbondioxide can be converted, by reaction with hydrogen, into fine chemicals and liquid fuels such as methanol and DME. Methane production by the Sabatier reaction opens the way of carbon recycling for a circular economy of carbon resources. The catalytic process of methanation of carbondioxide produces two molecules of water as a by-product. A current limitation in the CO 2 methanation is the ageing of catalysts, mainly due to water adsorption during the process. To avoid this adsorption, the process is operated at high temperature (300 °C–400 °C), leading to carbon deposition on the catalyst and its deactivation. To overcome this problem, a methanation plasma-catalytic process has been developed, which achieves high CO 2 conversion rate (80%), and a selectivity close to 100%, working from room temperature to 150 °C, instead of 300 °C–400 °C for the thermal catalytic process. The main characteristics of this process are high-voltage pulses of few nanoseconds duration, activating the adsorption of CO 2 in bent configuration and the polarization of the catalyst. The key step in this process is the desorption of water from the polarized catalyst. The high CO 2 conversion at low temperature could be explained by the creation of a plasma inside the nanopores of the catalyst. (paper)

Carbondioxide can be converted, by reaction with hydrogen, into fine chemicals and liquid fuels such as methanol and DME. Methane production by the Sabatier reaction opens the way of carbon recycling for a circular economy of carbon resources. The catalytic process of methanation of carbondioxide produces two molecules of water as a by-product. A current limitation in the CO2 methanation is the ageing of catalysts, mainly due to water adsorption during the process. To avoid this adsorption, the process is operated at high temperature (300 °C-400 °C), leading to carbon deposition on the catalyst and its deactivation. To overcome this problem, a methanation plasma-catalytic process has been developed, which achieves high CO2 conversion rate (80%), and a selectivity close to 100%, working from room temperature to 150 °C, instead of 300 °C-400 °C for the thermal catalytic process. The main characteristics of this process are high-voltage pulses of few nanoseconds duration, activating the adsorption of CO2 in bent configuration and the polarization of the catalyst. The key step in this process is the desorption of water from the polarized catalyst. The high CO2 conversion at low temperature could be explained by the creation of a plasma inside the nanopores of the catalyst.

This bachelor thesis examines and models the emissions of carbondioxide equivalents of the composition of automobiles in Sweden 2012. The report will be based on three scenarios of electricity valuation principles, which are a snapshot perspective, a retrospective perspective and a future perspective. The snapshot perspective includes high and low values for electricity on the margin, the retrospective perspective includes Nordic and European electricity mix and the future perspective includ...

In situ neutron diffraction measurements of adsorbed carbondioxide in an ordered mesoporous carbon (CMK-1) have been carried out along an isotherm at 253 K and at a range of pressures up to 18 bar. The experiment has been performed with the aid of a novel high-pressure adsorption apparatus and the GEM diffractometer (ISIS, Rutherford Appleton Laboratory, UK). Diffraction measurements of bulk liquid carbondioxide have also been carried out. The structure factors and the total differential correlation functions of the adsorbed carbondioxide suggest that the confined fluid has liquid-like properties at all thermodynamic states studied; however, some subtle differences were observed pointing to enhanced adsorption because of the presence of micropores.

Full Text Available Inability to secure the airway of a patient after induction of anaesthesia may lead to serious consequences including permanent brain damage and even death. Hypoxia is quite common in difficult intubations especially when it is difficult to ventilate the patient. However, carbondioxide retention severe enough to cause carbondioxide narcosis and delayed recovery is a rare occurrence. Here, we report a case of a craniovertebral junction anomaly where inadequate ventilation after induction of anaesthesia resulted in carbondioxide narcosis and delayed awakening. A 54-year-old, American Society of Anesthesiologists II female patient weighing 70 kg with a diagnosis of craniovertebral junction was scheduled for implant removal for dislodged occipital screw. Fibreoptic intubation was attempted after induction of anaesthesia and muscle paralysis. Even after multiple attempts, intubation could not be done and ventilation by face mask became difficult. Though oxygen saturation could be maintained with the insertion of a laryngeal mask airway (LMA, ventilation was not adequate. The patient remained unresponsive long after discontinuation of anaesthetic agent and reversal of muscle paralysis. Subsequent blood gas analysis showed severe carbondioxide retention and respiratory acidosis. Patient was given assist control mechanical ventilation through LMA. LMA was removed after improvement in sensorium and the blood gas picture.

“Unconventional reservoirs” for carbondioxide (CO2) storage—that is, geologic reservoirs in which changes to the rock trap CO2 and therefore contribute to CO2 storage—including coal, shale, basalt, and ultramafic rocks, were the focus of a U.S. Geological Survey (USGS) workshop held March 28 and 29, 2012, at the National Conservation Training Center in Shepherdstown, West Virginia. The goals of the workshop were to determine whether a detailed assessment of CO2 storage capacity in unconventional reservoirs is warranted, and if so, to build a set of recommendations that could be used to develop a methodology to assess this storage capacity. Such an assessment would address only the technically available resource, independent of economic or policy factors. At the end of the workshop, participants agreed that sufficient knowledge exists to allow an assessment of the potential CO2 storage resource in coals, organic-rich shales, and basalts. More work remains to be done before the storage resource in ultramafic rocks can be meaningfully assessed.

The viscosities of carbondioxide and xenon have been measured near their critical points and the critical exponent y characterizing the asymptotic divergence has been determined. Both fluids yielded exponents in the range y = 0.041 + or - 0.001 and thus also fell in the range y = 0.042 + or - 0.002 from an earlier study of four binary liquids. This agreement between experiments is the first evidence that pure fluids and binary liquids are in the same dynamic universality class. A recent theoretical value for y is 0.032. The 30 percent discrepancy is much greater than the combined errors from experiment and theory. The torsion oscillator viscometer operated at low frequency and low shear rate to avoid systematic errors caused by critical slowing down. Far from T(c) the analysis accounted for the crossover from critical to noncritical temperature dependence, where the latter was obtained from previously published correlations. Corrections for gravitational stratification were included close to T(c).

The goal of the Department of Energy (DOE) CarbonDioxide Research Program is to identify possible policy options for government action in response to effects of increased CO 2 . The achievement of this goal requires a significant increase in our scientific knowledge of the atmosphere, the biosphere, the oceans, and the cryosphere-their interactions and the effects that increasing atmospheric CO 2 and other trace gases will have on them. To identify and specify valid choices, a program of directed research is required. The research areas include: Projection of future atmospheric CO 2 concentrations Estimation of Co 2 -induced global/regional climate changes Estimation of crop and ecosystem response to CO 2 -induced changes Estimation of the effect of CO 2 -induced climate changes on sea level, fisheries, and human health. This paper describes the present DOE plan to address the questions related to the global and regional rate of CO 2 -induced climate change. The objective of the plan is to define the key questions in such a way that research is directed at experiments where answers are needed rather than at experiments where answers can be easily obtained. Only through this kind of focus can we expect to provide the climate-change estimates required for the policy process

River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle. A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbondioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial ecosystems. It is generally assumed that inland waters emit carbon that has been previously fixed upstream by land plant photosynthesis, then transferred to soils, and subsequently transported downstream in run-off. But at the scale of entire drainage basins, the lateral carbon fluxes carried by small rivers upstream do not account for all of the CO2 emitted from inundated areas downstream. Three-quarters of the world's flooded land consists of temporary wetlands, but the contribution of these productive ecosystems to the inland water carbon budget has been largely overlooked. Here we show that wetlands pump large amounts of atmospheric CO2 into river waters in the floodplains of the central Amazon. Flooded forests and floating vegetation export large amounts of carbon to river waters and the dissolved CO2 can be transported dozens to hundreds of kilometres downstream before being emitted. We estimate that Amazonian wetlands export half of their gross primary production to river waters as dissolved CO2 and organic carbon, compared with only a few per cent of gross primary production exported in upland (not flooded) ecosystems. Moreover, we suggest that wetland carbon export is potentially large enough to account for at least the 0.21 petagrams of carbon emitted per year as CO2 from the central Amazon River and its floodplains. Global carbon budgets should explicitly address temporary or vegetated flooded areas, because these ecosystems combine high aerial primary production with large, fast carbon export, potentially supporting a substantial fraction of CO2 evasion from inland waters.

Reducing anthropogenic carbondioxide (CO2) emissions into the atmosphere is a key challenge for society. Geological CO2 storage in deep saline aquifers is one of the most promising solutions to decrease carbon emissions. One such deep saline aquifer targeted for industrial-scale CO2 injection is the Basal Aquifer of Prairie Region in Canada and Northern Plains in the US. The aquifer stretches across three provinces (Alberta, Saskatchewan and Manitoba) and three states (Montana, North and South Dakota), and covers approximately 1,320,000 km2 (Figure 1). A large number of stationary CO2 sources lie within the foot print of the aquifer, and several CO2 injection projects are in the planning stage. In order for CO2 sequestration to be successful, the injected CO2 needs to stay isolated from the atmosphere for many centuries. Mathematical models are useful tools to assess the fate of both the injected CO2 and the resident brine. These models vary in complexity from fully three-dimensional multi-phase numerical reservoir simulators to simple semi-analytical solutions. In this presentation we compare a cascade of models ranging from single-phase semi-analytic solutions to multi-phase numerical simulators to determine the ability of each of these approaches to predict the pressure response in the injection formation. The majority of the models in this study are based on vertically-integrated governing equations; such models are computationally efficient, allow for reduced data input, and are broadly consistent with the flow physics. The petro-physical parameters and geometries used in this study are based on the geology of the Canadian section of the Basal Aquifer. Approximately ten injection sites are included in the model, with locations and injection rates based on planned injection operations. The predicted areas of review of the injection operations are used as a comparison metric among the different simulation approaches. Areal extent of the Basal Aquifer (*Source

Volatile solubility in magmas increases with pressure, although the solubility of CO2 is much lower than that of H2O. Consequently, magmas rising from depth release CO2-rich fluids, which inevitably interact with H2O-poor magmas in the upper crust (CO2-flushing). CO2-flushing triggers the exsolution of H2O-rich fluids, leading to an increase of volume and magma crystallisation. While the analyses of eruptive products demonstrates that this process operates in virtually all magmatic system, its impact on magmatic and volcanic processes has not been quantified. Here we show that depending on the initial magma crystallinity, and the depth of magma storage, CO2-flushing can lead to volcanic eruptions or promote conditions that favour the impulsive release of mineralising fluids. Our calculations show that the interaction between a few hundred ppm of carbonic fluids, and crystal-poor magmas stored at shallow depths, produces rapid pressurisation that can potentially lead to an eruption. Further addition of CO2 increases magma compressibility and crystallinity, reducing the potential for volcanic activity, promoting the formation of ore deposits. Increasing the depth of fluid-magma interaction dampens the impact of CO2-flushing on the pressurisation of a magma reservoir. CO2-flushing may result in surface inflation and increases in surface CO2 fluxes, which are commonly considered signs of an impending eruption, but may not necessarily result in eruption depending on the initial crystallnity and depth of the magmatic reservoir. We propose that CO2-flushing is a powerful agent modulating the pressurisation of magma reservoirs and the release of mineralising fluids from upper crustal magma reservoirs.

Carbondioxide and the carbonates, the available natural C1 sources, can be easily hydrogenated into formic acid and formates in water; the rate of this reduction strongly depends on the pH of the solution. This reaction is catalysed by ruthenium(II) pre-catalyst complexes with a large variety of water-soluble phosphine ligands; high conversions and turnover numbers have been realised. Although ruthenium(II) is predominant in these reactions, the iron(II) - tris[(2-diphenylphosphino)-ethyl]phosphine (PP3) complex is also active, showing a new perspective to use abundant and inexpensive iron-based compounds in the CO2 reduction. In the catalytic hydrogenation cycles the in situ formed metal hydride complexes play a key role, their structures with several other intermediates have been proven by multinuclear NMR spectroscopy. In the other hand safe and convenient hydrogen storage and supply is the fundamental question for the further development of the hydrogen economy; and carbondioxide has been recognised to be a viable H2 vector. Formic acid--containing 4.4 weight % of H2, that is 53 g hydrogen per litre--is suitable for H2 storage; we have shown that in aqueous solutions it can be selectively decomposed into CO-free (CO formic acid cleavage, in environmentally friendly propylene carbonate solution, opening the way to use cheap, non-noble metal based catalysts for this reaction, too.

The tar, nicotine, carbon monoxide, and carbondioxide contents of the smokes of 220 brands of foreign commercial cigarettes are reported. In some instances, filter cigarettes of certain brands were found to deliver as much or more smoke constituents than their nonfilter counterparts. Also, data indicated that there can be a great variation in the tar, nicotine, or carbon monoxide content of the smoke of samples of a given brand of cigarettes, depending on the nation in which they are purchased. 24 tables.

This paper is an attempt to provide a summary review of conclusions from previous studies on this subject. Subject headings include: conceptualization of the greenhouse effect, the climatic effect of doubled CO/sub 2/, interpretation of the climatic record, diagnosis of apparent and possible model deficiencies, and the palaeoclimatic record.

This paper is an attempt to provide a summary review of conclusions from previous studies on this subject. Subject headings include: conceptualization of the greenhouse effect, the climatic effect of doubled CO 2 , interpretation of the climatic record, diagnosis of apparent and possible model deficiencies, and the palaeoclimatic record

This state-of-the-art volume presents discussions on the global cycle of carbon, the dynamic balance among global atmospheric CO2 sources and sinks. Separate abstracts have been prepared for the individual papers. (ACR)

A pilot carbondioxide miscible flood was initiated in the Lansing Kansas City C formation in the Hall Gurney Field, Russell County, Kansas. Continuous carbondioxide injection began on December 2, 2003. By the end of June 2004, 6.26 MM lb of carbondioxide were injected into the pilot area. Carbondioxide injection rates averaged about 250 MCFD. Carbondioxide was detected in one production well near the end of May. The amount of carbondioxide produced was small during this period. Wells in the pilot area produced 100% water at the beginning of the flood. Oil production began in February, increasing to an average of about 2.5 B/D in May and June. Operational problems encountered during the initial stages of the flood were identified and resolved.

The International Space Station (ISS) represents a largely closed-system habitable volume which requires active control of atmospheric constituents, including removal of exhaled CarbonDioxide (CO2). The ISS provides a unique opportunity to observe system requirements for (CO2) removal. CO2 removal is managed by the CarbonDioxide Removal Assembly (CDRA) aboard the US segment of ISS and by Lithium Hydroxide (LiOH) aboard the Space Shuttle (STS). While the ISS and STS are docked, various methods are used to balance the CO2 levels between the two vehicles, including mechanical air handling and management of general crew locations. Over the course of ISS operation, several unexpected anomalies have occurred which have required troubleshooting, including possible compromised performance of the CDRA and LiOH systems, and possible imbalance in CO2 levels between the ISS and STS while docked. This paper will cover efforts to troubleshoot the CO2 removal systems aboard the ISS and docked STS.

Geologic sequestration of CO2 generated from fossil fuel combustion may be an environmentally attractive method to reduce the amount of greenhouse gas emissions. Of the geologic options, sequestering CO2 in coal beds has several advantages. For example, CO2 injection can enhance methane production from coal beds; coal can trap CO2 for long periods of time; and potential major coal basins that contain ideal beds for sequestration are near many emitting sources of CO2.One mission of the Energy Resources Program of the U.S. Geological Survey is to maintain assessment information of the Nation’s resources of coal, oil, and gas. The National Coal Resources Assessment Project is currently completing a periodic assessment of 5 major coal-producing regions of the US. These regions include the Powder River and Williston and other Northern Rocky Mountain basins (Fort Union Coal Assessment Team, 1999), Colorado Plateau area (Kirschbaum and others, 2000), Gulf Coast Region, Appalachian Basin, and Illinois Basin. The major objective of this assessment is to estimate available coal resources and quality for the major producing coal beds of the next 25 years and produce digital databases and maps. Although the focus of this work has been on coal beds with the greatest potential for mining, it serves as a basis for future assessments of the coal beds for other uses such as coal bed methane resources, in situ gasification, and sites for sequestration of CO2. Coal bed methane production combined with CO2 injection and storage expands the use of a coal resource and can provide multiple benefits including increased methane recovery, methane drainage of a resource area, and the long-term storage of CO2.

The authors report the observation of a 43-year-old woman with severe pain on her right upper abdominal quadrant. Differential diagnoses included acute cholecystitis, spontaneous pneumothorax, perforated appendicitis and a recidive of renal calculus. CT-scan showed a huge subdermal gas bubble along her right flank and anterior abdominal wall up to the submammary fold. Only at this point, the patient admitted to have undergone a carboxytherapy procedure on both thighs one day before onset of pain in a paramedical facility. As some of the injection trajects were still patent on CT-scan, she received prophylactic antibiotic coverage. Though there was a complete resorption of gas after 10 days, dysesthesias and muscle contracture persisted for 3 weeks. To the authors' knowledge this migration and coalescence of injected gas in a single bubble has not been previously reported. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .

Evapo-transpiration from vegetation, as well as patterns of precipitation are expected to change as the concentration of CO(sub 2) in the atmosphere continues to rise (f). Water modulates the rates of many biogeochemical processes, and it has been estimated that water directly limits plant productivity over two-thirds of the earth's land surface (2). Water quality and availability are increasingly important practical issues as demands by both agricultural and urban users continue to increase. In a recent Perspective article (3) Farquhar stated that transpiration (water loss) from terrestrial vegetation will decline by 40 to 50% as the CO(sub 2) concentration in the atmosphere approaches twice present levels. He suggested that ''the impending saving of water would be a welcome result of the rising atmospheric CO(sub 2) concentration.'' We can confirm that large reductions in transpiration are expected by terrestrial physiological ecologists. Examining 35 recent articles that discussed the issue of water use while synthesizing research on ecosystem impacts of doubling atmospheric CO(sub 2) (including reviews and crop/natural ecosystem models), we found that 31 articles suggest that reductions in water use of between 25 and 50% are to be expected

Carbonic anhydrases (CAs) are enzymes that catalyze the hydration/ dehydration of CO2/HCO3- with rates approaching diffusion-controlled limits (kcat/KM ~ 108 M–1s–1). Here, this family of enzymes has evolved disparate protein folds that all perform the same reaction at near catalytic perfection. Presented here is a structural study of a beta-CA (psCA3) expressed in Pseudomonas aeruginosa, in complex with CO2, using pressurized cryocooled crystallography. The structure has been refined to 1.6 angstrom resolution with Rcryst and Rfree values of 17.3 and 19.9%, respectively, and is compared with the α-CA, human CA isoform II (hCA II), the only other CA to have CO2, captured in its active site. Despite the lack of structural similarity between psCA3 and hCA II, the CO2, binding orientation relative to the zinc-bound solvent is identical. In addition, a second CO2, binding site was located at the dimer interface of psCA3. Interestingly, all β-CAs function as dirners or higher-order oligomeric states, and the CO2, bound at the interface may contribute to the allosteric nature of this family of enzymes or may be a convenient alternative binding site as this pocket has been previously shown to be a promiscuous site for a variety of ligands, including bicarbonate, sulfate, and phosphate ions.

The direct synthesis of dimethyl carbonate from methanol and carbondioxide is challenging due to the thermodynamic stability and kinetic inertness of CO 2 . Electrochemical technique can overcome this challenge by providing a method for preliminary activation of CO 2 . Electrocatalytic activation and conversion of carbondioxide to dimethyl carbonate with platinum electrodes in a dialkylimidazolium ionic liquids-basic compounds-methanol system was conducted under ambient conditions. Among the basic compounds and ionic liquids, CH 3 OK acts as a co-catalyst and 1-butyl-3-methylimidazolium bromide (bmimBr) acts as an electrolyte. In the bmimBr-CH 3 OK-methanol system, the absence of CH 3 I and/or any other organic additives allows dimethyl carbonate to be effectively synthesized. The reaction mechanism proposed here is different from those previously reported

The objective of the present study was to determine the performance of CO{sub 2} microchannel evaporators and gas coolers in operational conditions representing those of residential heat pumps. A set of breadboard prototype microchannel evaporators and gas coolers was developed and tested. The refrigerant in the heat exchangers followed a counter cross-flow path with respect to the airflow direction. The test conditions corresponded to the typical operating conditions of residential heat pumps. In addition, a second set of commercial microchannel evaporators and gas coolers was tested for a less comprehensive range of operating conditions. The test results were reduced and a comprehensive data analysis, including comparison with the previous studies in this field, was performed. Capacity and pressure drop of the evaporator and gas cooler for the range of parameters studied were analyzed and are documented in this report. A gas cooler performance prediction model based on non-dimensional parameters was also developed and results are discussed as well. In addition, in the present study, experiments were conducted to evaluate capacities and pressure drops for sub-critical CO{sub 2} flow boiling and transcritical CO{sub 2} gas cooling in microchannel heat exchangers. An extensive review of the literature failed to indicate any previous systematic study in this area, suggesting a lack of fundamental understanding of the phenomena and a lack of comprehensive data that would quantify the performance potential of CO{sub 2} microchannel heat exchangers for the application at hand. All experimental tests were successfully conducted with an energy balance within {+-}3%. The only exceptions to this were experiments at very low saturation temperatures (-23 C), where energy balances were as high as 10%. In the case of evaporators, it was found that a lower saturation temperature (especially when moisture condensation occurs) improves the overall heat transfer coefficient

BACKGROUND—Carbondioxide concentration under ophthalmic drapes increases during eye surgery under local anaesthesia. A new prototype has been designed which combines continuous suction of carbondioxide enriched air and continuous oxygen insufflation under ophthalmic drapes to prevent carbondioxide accumulation in spontaneously breathing patients undergoing cataract surgery. METHODS—In a prospective randomised single blind study the effectiveness of this new prototype was examined in 50 unp...

As concerns about the environment are growing, new efforts are needed to achieve more sustainable processes. One such environmental concern is global warming, which is primarily caused by the greenhouse effect or the increase in concentration of greenhouse gases [1]. The most significant greenhouse gases are carbondioxide, methane and nitrous oxide, of which carbondioxide is the highest constituent at 82%. Furthermore, the amount of carbondioxide emissions is growing with time. These trend...

The objectives of the project is to develop technologies by which the flue gases from burning bio fuels and peat can be purified for used in green houses as a low cost source of carbondioxide. Traditionally carbondioxide has been produced by burning propane or natural gas or by injecting bottled carbondioxide gas directly into the green house. The new methods should be more affordable than the present ones. (orig.)

A primary objective of energy conservation is to cut carbondioxide emissions. A comparative study on the various heating forms, based on the life cycle approach, showed that the carbondioxide emissions resulting form heating are appreciably lower now that electric heating has become more common. The level of carbondioxide emissions in Finland would have been millions of tonnes higher had oil heating been chosen instead of electric heating. (orig.)

Fluids operating in the supercritical state have promising characteristics for future high efficiency power cycles. In order to develop power cycles using supercritical fluids, it is necessary to understand the flow characteristics of fluids under both supercritical and two-phase conditions. In this study, a Computational Fluid Dynamic (CFD) methodology was developed for supercritical fluids flowing through complex geometries. A real fluid property module was implemented to provide properties for different supercritical fluids. However, in each simulation case, there is only one species of fluid. As a result, the fluid property module provides properties for either supercritical CO2 (S-CO2) or supercritical water (SCW). The Homogeneous Equilibrium Model (HEM) was employed to model the two-phase flow. HEM assumes two phases have same velocity, pressure, and temperature, making it only applicable for the dilute dispersed two-phase flow situation. Three example geometries, including orifices, labyrinth seals, and valves, were used to validate this methodology with experimental data. For the first geometry, S-CO2 and SCW flowing through orifices were simulated and compared with experimental data. The maximum difference between the mass flow rate predictions and experimental measurements is less than 5%. This is a significant improvement as previous works can only guarantee 10% error. In this research, several efforts were made to help this improvement. First, an accurate real fluid module was used to provide properties. Second, the upstream condition was determined by pressure and density, which determines supercritical states more precise than using pressure and temperature. For the second geometry, the flow through labyrinth seals was studied. After a successful validation, parametric studies were performed to study geometric effects on the leakage rate. Based on these parametric studies, an optimum design strategy for the see

This study aimed to investigate the influence of carbonated drinks with gas volumes (GV) of 0, 1.5, and 2.7 on linguapalatal swallowing pressure, intraoral carbonation perception, and maximum velocity of a bolus through the pharynx in healthy volunteers (N = 20, all female, age range; 20-21 years). The volunteers swallowed a 12-mL drink in the natural state. Linguapalatal swallowing pressure was measured using a special sensor sheet, and maximum velocity of the bolus through the pharynx was measured using ultrasonic diagnostic imaging equipment. Peak magnitude, integrated value, and duration of linguapalatal swallowing pressure and maximum velocity of a liquid bolus through the pharynx increased with an increase in carbondioxide content in the carbonated drink. The total integrated values of carbonated drinks with GV of 1.5 and 2.7 were larger than that of the drink without carbondioxide. These results suggest that the carbondioxide dissolved in carbonated drinks influences the activity of taste receptors in the mouth and results in neuromotor responses.

This paper discusses the research progress of the second year of research under Measurement of Surface Ocean CarbonDioxide Partial Pressure During WOCE'' and proposes to continue measurements of underway pCO[sub 2]. During most of the first year of this grant, our efforts to measure pCO[sub 2] on WOCE WHP legs were frustrated by ship problems. The R/V Knorr, which was originally scheduled to carry out the first work on WHP lines P19 and P16 in the southeastem Pacific during the 1990-91 austral summer, was delayed in the shipyard during her mid-life refit for more than a year. In the interim, the smaller R/V Thomas Washington, was pressed into service to carry out lower-latitude portions of WHP lines P16 and P17 during mid-1991 (TUNES Expedition). We installed and operated our underway chromatographic system on this expedition, even though space and manpower on this smaller vessel were limited and no one from our group would be aboard any of the 3 WHP expedition legs. The results for carbondioxide and nitrous oxide are shown. A map of the cruise track is shown for each leg, marked with cumulative distance. Following each track is a figure showing the carbondioxide and nitrous oxide results as a function of distance along this track. The results are plotted as dry-gas mole fractions (in ppm and ppb, respectively) in air and in gas equilibrated with surface seawater at a total pressure equal to the barometric pressure. The air data are plotted as a 10-point running mean, and appear as a roughly horizontal line. The seawater data are plotted as individual points, using a 5-point Gaussian smoother. Equal values Of xCO[sub 2] in air and surface seawater indicate air-sea equilibrium.

Volcanic gases give information on magmatic processes. In particular, anomalous releases of carbondioxide precede volcanic eruptions. Up to now, this gas has been measured in volcanic plumes with conventional measurements that imply the severe risks of local sampling and can last many hours. For these reasons and for the great advantages of laser sensing, the thorough development of volcanic lidar has been undertaken at the Diagnostics and Metrology Laboratory (UTAPRAD-DIM) of the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA). In fact, lidar profiling allows one to scan remotely volcanic plumes in a fast and continuous way, and with high spatial and temporal resolution. Two differential absorption lidar instruments will be presented in this paper: BILLI (BrIdge voLcanic LIdar), based on injection seeded Nd:YAG laser, double grating dye laser, difference frequency mixing (DFM) and optical parametric amplifier (OPA), and VULLI (VULcamed Lidar), based on injection seeded Nd:YAG laser and optical parametric oscillator (OPO). The first one is funded by the ERC (European Research Council) project BRIDGE and the second one by the ERDF (European Regional Development Fund) project VULCAMED. While VULLI has not yet been tested in a volcanic site, BILLI scanned the gas emitted by Pozzuoli Solfatara (Campi Flegrei volcanic area, Naples, Italy) during a field campaign carried out from 13 to 17 October 2014. Carbondioxide concentration maps were retrieved remotely in few minutes in the crater area. Lidar measurements were in good agreement with well-established techniques, based on different operating principles. To our knowledge, it is the first time that carbondioxide in a volcanic plume is retrieved by lidar, representing the first direct measurement of this kind ever performed on an active volcano and showing the high potential of laser remote sensing in geophysical research.

National Aeronautics and Space Administration — Carbondioxide reduction is considered a major shortcoming for the current Atmosphere Revitalization System. Novel technologies are desired so that the oxygen...

The synthesis of three amine-based carbondioxide fixing reagents is presented. The reagents were designed so that they would be able to bind CO2 reversibly through the formation of the well known carbamates that was stabilized through forming a zwitterion. CO2 fixing experiments were performed...... with 13CO2 labeling and medium pressure NMR. The experiments showed that two of the three reagents were able to form carbamates and thus bind CO2. In addition we investigated this particular class of molecules for the possible formation of neutrally charged spiro compounds and we show that these did...

A long path, low pressure laboratory spectrum of carbondioxide is presented for the spectral region 1830 to 2010/cm. The data were recorded at 0.01/cm resolution and room temperature with the Fourier transform spectrometer in the McMath solar telescope complex at Kitt Peak National Observatory. A list of positions and assignments is given for the 1038 lines observed in this region. A total of 30 bands and subbands of 12C1602, 13C1602, 12C160180, 12C160170, and 13C160180 were observed. Previously announced in STAR as N83-19598

Carbondioxide selective membranes provide a viable energy-saving alternative for CO2 separation, since membranes do not require any phase transformation. This review examines various CO2 selective membranes for the separation of CO2 and N2, CO2 and CH4, and CO2 and H2 from flue or fuel gas. This review attempts to summarize recent significant advances reported in the literature about various CO2 selective membranes, their stability, the effect of different parameters on the performance of the membrane, the structure and permeation properties relationships, and the transport mechanism applied in different CO2 selective membranes.

This paper examines available data, develops a strategy and presents a monthly, global time series of fossil-fuel carbondioxide emissions for the years 1950–2006. This monthly time series was constructed from detailed study of monthly data from the 21 countries that account for approximately 80......% of global total emissions. These data were then used in a Monte Carlo approach to proxy for all remaining countries. The proportional-proxy methodology estimates by fuel group the fraction of annual emissions emitted in each country and month. Emissions from solid, liquid and gas fuels are explicitly...

The paper examines the TIR-1 carbondioxide laser system for fusion. The current efforts are concentrated on (1) the microsecond laser pulse plasma heating in solenoids and theta pinches, and (2) nanosecond CO2 laser utilization for inertial confinement fusion. The TIR-1 system was designed to develop nanosecond CO2 laser technology and to study laser-target interaction at 10 microns. This system consists of an oscillator-preamplifier that produces about 1-nsec laser pulse with an energy contrast ratio of 1 million, a large triple-pass amplifier, and a target chamber with diagnostic equipment.

Based on conventional mass transfer models developed for oxygen, the use of the non-linear ASCE method, 2-point method, and one parameter linear-regression method were evaluated for carbondioxide stripping data. For values of KLaCO2 down at higher values of KLaCO2. How to correct KLaCO2 for gas phase enrichment remains to be determined. The one-parameter linear regression model was used to vary the C*CO2 over the test, but it did not result in a better fit to the experimental data when compared to the ASCE or fixed C*CO2 assumptions.

New and Future Developments in Catalysis is a package of books that compile the latest ideas concerning alternate and renewable energy sources and the role that catalysis plays in converting new renewable feedstock into biofuels and biochemicals. Both homogeneous and heterogeneous catalysts and catalytic processes will be discussed in a unified and comprehensive approach. There will be extensive cross-referencing within all volumes. This volume presents a complete picture of all carbondioxide (CO2) sources, outlines the environmental concerns regarding CO2, and critica

The direct approach: Methane is a potential key player in the world's transition to a more sustainable energy future. The direct conversion of carbondioxide into methane is highly desirable to lower the concentration of CO{sub 2} in the atmosphere and also to store renewable energy. This Highlight describes the first homogeneous system for the light-driven conversion of CO{sub 2} into CH{sub 4}. (copyright 2018 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

The solubility of 93% pure bixin in supercritical carbondioxide (SC-CO2) and of the bixin present in annatto seeds (Bixa orellana L.) was measured. For the seeds, the measurements were made in a temperature range from 30 to 50ºC and pressure between 10 and 35 MPa and for the pure bixin, at 40ºC from 10 to 35 MPa. The main pigments of annatto seeds are bixin and norbixin, but the extracts only showed the presence of cis and trans-bixin, indicating that norbixin is not soluble in SC-CO2. The a...

Ongoing global warming could persist far into the future, because natural processes require decades to hundreds of thousands of years to remove carbondioxide from fossil-fuel burning from the atmosphere(1-3). Future warming may have large global impacts including ocean oxygen depletion and assoc......Ongoing global warming could persist far into the future, because natural processes require decades to hundreds of thousands of years to remove carbondioxide from fossil-fuel burning from the atmosphere(1-3). Future warming may have large global impacts including ocean oxygen depletion...... solubility from surface-layer warming accounts for most of the enhanced oxygen depletion in the upper 500 m of the ocean. Possible weakening of ocean overturning and convection lead to further oxygen depletion, also in the deep ocean. We conclude that substantial reductions in fossil-fuel use over the next...

The Surface Ocean CO2 Atlas (SOCAT) is an activity by the international marine carbon research community. It improves access to surface water CO2 data by regular releases of quality controlled and documented, synthesis fCO2 (fugacity of carbondioxide) data products for the global surface oceans and coastal seas. The first version of SOCAT was publicly released in September 2011(Bakker et al., 2011) with 6.3 million observations. In June 2013 version 2 was released including already over 10 million observations and in September 2015 SOCAT version 3 was released with more than 14 million observations. With the release of version 3 in September 2015 a big step was made in the direction of an annual updated database by using an automated data ingestion and quality control tool. The database holds now data from 1957 to today which enables SOCAT data products the detection of changes in the ocean carbon sink. Here we present the innovations in version 3 and give an outlook of the next version(s) of SOCAT. A major improvement in version 3 is the inclusion of data from alternative sensors with a lower accuracy (better than 10 µatm) compared to the standard instrumentation (2 µatm), since their number will increase in the future. In addition exemplary studies using the SOCAT database will be presented which demonstrate the potential of the SOCAT database and point out possible improvements for the future.

A two-dimensional (latitude-altitude) model of atmospheric CO 2 and δ 13 C was constructed to simulate some features of seasonal carbon cycle fluctuations. The model simulates air-sea exchange, atmospheric diffusion, and fossil fuel carbon sources, which are functions of time and latitude. In addition, it uses biosphere-atmosphere fluxes of carbon that are based on global-scale biological models of vegetation growth and decay. Results of the model show fair agreement with observational results for CO 2 and δ 13 C seasonal fluctuations. Their model results have far northern fluctuations with smaller amplitudes than are observed. Analysis of sources of CO 2 change at given latitudes shows that, for far southern latitudes, southern hemisphere biospheric fluxes are dominant in affecting the seasonal CO 2 fluctuations. Long-term decrease of δ 13 C for the model is larger than for observations. This may be due to errors in the formulation for oceanic fluxes for 13 C in the model or to a net uptake of carbon by the biosphere

Various proxies (such as pedogenic carbonates, boron isotopes or phytoplankton) and geochemical models were applied in order to reconstruct palaeoatmospheric carbondioxide, partially providing conflicting results. Another promising proxy is the frequency of stomata (pores on the leaf surface used for gaseous exchange). In this project, fossil plant material from the Messel Pit (Hesse, Germany) is used to reconstruct atmospheric carbondioxide concentration in the Middle Eocene by analyzing stomatal density. We applied the novel mechanistic-theoretical approach of Konrad et al. (2008) which provides a quantitative derivation of the stomatal density response (number of stomata per leaf area) to varying atmospheric carbondioxide concentration. The model couples 1) C3-photosynthesis, 2) the process of diffusion and 3) an optimisation principle providing maximum photosynthesis (via carbondioxide uptake) and minimum water loss (via stomatal transpiration). These three sub-models also include data of the palaeoenvironment (temperature, water availability, wind velocity, atmospheric humidity, precipitation) and anatomy of leaf and stoma (depth, length and width of stomatal porus, thickness of assimilation tissue, leaf length). In order to calculate curves of stomatal density as a function of atmospheric carbondioxide concentration, various biochemical parameters have to be borrowed from extant representatives. The necessary palaeoclimate data are reconstructed from the whole Messel flora using Leaf Margin Analysis (LMA) and the Coexistence Approach (CA). In order to obtain a significant result, we selected three species from which a large number of well-preserved leaves is available (at least 20 leaves per species). Palaeoclimate calculations for the Middle Eocene Messel Pit indicate a warm and humid climate with mean annual temperature of approximately 22°C, up to 2540 mm mean annual precipitation and the absence of extended periods of drought. Mean relative air

In this work, sewage sludge was used as precursor in the production of activated carbon by means of chemical activation with KOH and NaOH. The sludge-based activated carbons were investigated for their gaseous adsorption characteristics using CO2 as adsorbate. Although both chemicals were effective in the development of the adsorption capacity, the best results were obtained with solid NaOH (SBA(T16)). Adsorption results were modeled according to the Langmuir and Freundlich models, with resulting CO2 adsorption capacities about 56 mg/g. The SBA(T16) was characterized for its surface and pore characteristics using continuous volumetric nitrogen gas adsorption and mercury porosimetry. The results informed about the mesoporous character of the SBA(T16) (average pore diameter of 56.5 angstroms). The Brunauer-Emmett-Teller (BET) surface area of the SBA(T16) was low (179 m2/g) in comparison with a commercial activated carbon (Airpel 10; 1020 m2/g) and was mainly composed of mesopores and macropores. On the other hand, the SBA(T16) adsorption capacity was higher than that of Airpel 10, which can be explained by the formation of basic surface sites in the SBA(T16) where CO2 experienced chemisorption. According to these results, it can be concluded that the use of sewage-sludge-based activated carbons is a promising option for the capture of CO2. Adsorption methods are one of the current ways to reduce CO2 emissions. Taking this into account, sewage-sludge-based activated carbons were produced to study their CO2 adsorption capacity. Specifically, chemical activation with KOH and NaOH of previously pyrolyzed sewage sludge was carried out. The results obtained show that even with a low BET surface area, the adsorption capacity of these materials was comparable to that of a commercial activated carbon. As a consequence, the use of sewage-sludge-based activated carbons is a promising option for the capture of CO2 and an interesting application for this waste.

Lung engineering is a potential alternative to transplantation for patients with end-stage pulmonary failure. Two challenges critical to the successful development of an engineered lung developed from a decellularized scaffold include (i) the suppression of resident infectious bioburden in the lung matrix, and (ii) the ability to sterilize decellularized tissues while preserving the essential biological and mechanical features intact. To date, the majority of lungs are sterilized using high concentrations of peracetic acid (PAA) resulting in extracellular matrix (ECM) depletion. These mechanically altered tissues have little to no storage potential. In this study, we report a sterilizing technique using supercritical carbondioxide (ScCO2) that can achieve a sterility assurance level 10(-6) in decellularized lung matrix. The effects of ScCO2 treatment on the histological, mechanical, and biochemical properties of the sterile decellularized lung were evaluated and compared with those of freshly decellularized lung matrix and with PAA-treated acellular lung. Exposure of the decellularized tissue to ScCO2 did not significantly alter tissue architecture, ECM content or organization (glycosaminoglycans, elastin, collagen, and laminin), observations of cell engraftment, or mechanical integrity of the tissue. Furthermore, these attributes of lung matrix did not change after 6 months in sterile buffer following sterilization with ScCO2, indicating that ScCO2 produces a matrix that is stable during storage. The current study's results indicate that ScCO2 can be used to sterilize acellular lung tissue while simultaneously preserving key biological components required for the function of the scaffold for regenerative medicine purposes.

A method for producing liquid fuels includes the steps of gasifying a starting material selected from a group consisting of coal, biomass, carbon nanotubes and mixtures thereof to produce a syngas, subjecting that syngas to Fischer-Tropsch synthesis (FTS) to produce a hyrdrocarbon product stream, separating that hydrocarbon product stream into C1-C4 hydrocarbons and C5+ hydrocarbons to be used as liquid fuels and subjecting the C1-C4 hydrocarbons to catalytic dehydrogenation (CDH) to produce hydrogen and carbon nanotubes. The hydrogen produced by CDH is recycled to be mixed with the syngas incident to the FTS reactor in order to raise the hydrogen to carbon monoxide ratio of the syngas to values of 2 or higher, which is required to produce liquid hydrocarbon fuels. This is accomplished with little or no production of carbondioxide, a greenhouse gas. The carbon is captured in the form of a potentially valuable by-product, multi-walled carbon nanotubes (MWNT), while huge emissions of carbondioxide are avoided and very large quantities of water employed for the water-gas shift in traditional FTS systems are saved.

Initial plans for research of the carbondioxide (CO/sub 2/) and climate issue were prepared in 1978 and were reviewed extensively at that time by federal agencies and members of the scientific community. Since then the plans have been used to guide early phases of the Department of Energy's and the nation's efforts related to this issue. This document represents a revision of the 1978 plan to (a) reflect recent ideas and strategies for carbon cycle research, and (b) expand the scope of research on climatic responses to increasing atmospheric concentrations of CO/sub 2/. The revised plan takes into account a number of investigations already being supported by various agencies, and it attempts to build on or add to existing research where there is a crucial need for information directly related to the CO/sub 2/ issue. It should be recognized that this document is the first section of a comprehensive plan on the overall consequences of increasing concentrations of CO/sub 2/, and includes guidelines for research on the Global Carbon Cycle and Climatic Effects of Increasing CO/sub 2/.

The clinical practice of using carbondioxide therapy for localized adiposities was audited over a 4-year period. Patients receiving physical, dietary, or drug concurrent therapy were excluded from the audit. Original measurements in terms of mean +/- standard error of the mean (SEM) were compared with those obtained after five sessions. This series included 101 women who underwent abdominal therapy. Significant reduction (p carboxytherapy is safe and effective.

Research continued into the investigation of the effects of carbondioxide on stomatal control of water balance and photosynthesis in higher plants. Topics discussed this period include a method of isolating a sufficient number of guard cell chloroplasts for biochemical studies by mechanical isolation of epidermal peels; the measurement of stomatal apertures with a digital image analysis system; development of a high performance liquid chromatography method for quantification of metabolites in guard cells; and genetic control of stomatal movements in Pima cotton. (CBS)

A one-pot, two-step protocol for the direct synthesis of polyurethanes containing few carbonate linkages through polycondensation of diamines, dihalides, and CO2 in the presence of Cs2CO3 and tetrabutylammonium bromide is described. The conditions were optimized by studying the polycondensation of CO2 with 1,6-hexanediamine and 1,4-dibromobutane as model monomers. Then, various diamines and dihalides were tested under optimal conditions. Miscellaneous samples of such carbonate-containing polyurethanes exhibiting molar masses from 6000 to 22 000 g/mol (GPC) and yields higher than 85% were obtained. The thermal properties of such polyurethanes were unveiled by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA): they were found very similar to those of traditional polyurethanes obtained by diisocyanates + diols polycondensation.

London, with a population of 8.2 million, is the largest city in Europe. It is heavily built-up (typically 8% vegetation cover within the central boroughs) and boasts some of the busiest arteries in Europe despite efforts to reduce traffic in the city centre with the introduction of a congestion charging scheme in 2007. We report on two substantial pollution monitoring efforts in the heart of London between October 2006 and present. Fluxes of carbondioxide (CO2) and water (H2O) were measured continuously by eddy-covariance in central London from October 2006 until May 2008 from a 190 m telecommunication tower (BT tower; 51° 31' 17.4'' N 0° 8' 20.04'' W). The eddy-covariance system consisted of a Gill R3-50 ultrasonic anemometer operated at 20 Hz and a LI-COR 6262 infrared gas analyser. Air was sampled 0.3 m below the sensor head of the ultrasonic anemometer - which was itself mounted on a 3 m mast to the top of a 15 m lattice tower situated on the roof of the tower (instrument head at 190 m above street level) - and pulled down 45 m of 12.7 mm OD Teflon tubing. In addition, meteorological variables (temperature, relative humidity, pressure, precipitation, wind speed and direction) were also measured with a multi-sensor (Weather Transmitter WXT510, Vaisala). Eddy-covariance measurements at the BT tower location were reinstated in July 2011 and include methane (CH4), CO2 and H2O concentrations measured by a Picarro fast methane analyser (G2301-f). CO2 emissions were found to be mainly controlled by fossil fuel combustion (e.g. traffic, commercial and domestic heating). Diurnal averages of CO2 fluxes were found to be highly correlated to traffic. However changes in heating-related natural gas consumption and, to a lesser extent, photosynthetic activity in two large city centre green spaces (Hyde Park and Regent's Park) explained the seasonal variability. Annual estimates of net exchange of CO2 obtained by eddy-covariance agreed well with up-scaled data from the UK

The successful transition to a low-carbon economy hinges on innovative solutions and collaborative action on a global scale. Sustainable entrepreneurship is thereby recognized as a key driver in the creation and transformation of ecologically and socially sustainable economic systems. The purpose of this article is to contribute to this topic by understanding commercialization barriers for strong sustainability-oriented new technology ventures and to derive recommendations to overcome them. A qualitative multilevel approach is applied to identify barriers and drivers within the internal dynamic capabilities of the organization and within the organization’s external stakeholders. A model of barriers has been developed based on semi-structured interviews with new carbondioxide utilization ventures and associated industry players in Canada, the USA, and the European Economic Area. Resulting recommendations to facilitate the (re-)design of a dedicated support system are proposed on four levels: (a) actors, (b) resources, (c) institutional settings, and (d) the coordination of the support system.

The successful transition to a low-carbon economy hinges on innovative solutions and collaborative action on a global scale. Sustainable entrepreneurship is thereby recognized as a key driver in the creation and transformation of ecologically and socially sustainable economic systems. The purpose of this article is to contribute to this topic by understanding commercialization barriers for strong sustainability-oriented new technology ventures and to derive recommendations to overcome them. A qualitative multilevel approach is applied to identify barriers and drivers within the internal dynamic capabilities of the organization and within the organization’s external stakeholders. A model of barriers has been developed based on semi-structured interviews with new carbondioxide utilization ventures and associated industry players in Canada, the USA, and the European Economic Area. Resulting recommendations to facilitate the (re-)design of a dedicated support system are proposed on four levels: (a) actors, (b) resources, (c) institutional settings, and (d) the coordination of the support system.

Photocatalysis has not found widespread industrial adoption, in spite of decades of active research, because the challenges associated with catalyst illumination and turnover outweigh the touted advantages of replacing heat with light. A demonstration that light can control product selectivity in complex chemical reactions could prove to be transformative. Here, we show how the recently demonstrated plasmonic behaviour of rhodium nanoparticles profoundly improves their already excellent catalytic properties by simultaneously reducing the activation energy and selectively producing a desired but kinetically unfavourable product for the important carbondioxide hydrogenation reaction. Methane is almost exclusively produced when rhodium nanoparticles are mildly illuminated as hot electrons are injected into the anti-bonding orbital of a critical intermediate, while carbon monoxide and methane are equally produced without illumination. The reduced activation energy and super-linear dependence on light intensity cause the unheated photocatalytic methane production rate to exceed the thermocatalytic rate at 350 °C. PMID:28230100

Natural gas conversion remains one of the essential technologies for current energy needs. This review focuses on the mechanistic aspects of the development of efficient and durable catalysts for two reactions, carbondioxide reforming and the oxidative coupling of methane. These two reactions have tremendous technological significance for practical application in industry. An understanding of the fundamental aspects and reaction mechanisms of the catalytic reactions reviewed in this study would support the design of industrial catalysts. CO 2 reforming of methane utilizes CO 2, which is often stored in large quantities, to convert as a reactant. Strategies to eliminate carbon deposition, which is the major problem associated with this reaction, are discussed. The oxidative coupling of methane directly produces ethylene in one reactor through a slightly exothermic reaction, potentially minimizing the capital cost of the natural gas conversion process. The focus of discussion in this review will be on the attainable yield of C 2 products by rigorous kinetic analyses.

We have developed and validated a statistical model to estimate the fugacity (or partial pressure) of carbondioxide (CO2) at sea surface (pCO2sea) from space-based observations of sea surface temperature (SST), chlorophyll, and salinity. More than a quarter million in situ measurements coincident with satellite data were compiled to train and validate the model. We have produced and made accessible 9 years (2002-2010) of the pCO2sea at 0.5 degree resolutions daily over the global ocean. The results help to identify uncertainties in current JPL Carbon Monitoring System (CMS) model-based and bottom-up estimates over the ocean. The utility of the data to reveal multi-year and regional variability of the fugacity in relation to prevalent oceanic parameters is demonstrated.

This paper, written in French and in English, examines how the figures have changed from Kyoto base year 1990 up to 2007, before looking at certain countries' proposals for the future of their carbondioxide emissions. Statistics are given concerning the emissions changes in various countries (or groups of countries) but also their developments in regards to the economy and energy use. Changes in CO 2 emissions, changes in the gross domestic product of a country, its CO 2 emissions per capita, its energy intensity (the ratio of energy use to the monetary value of GDP) and its carbon intensity of energy use as well as population change, are presented. The main countries considered are: United States, European Union, China, Japan, India, Brazil, South Africa and Russia

Photocatalysis has not found widespread industrial adoption, in spite of decades of active research, because the challenges associated with catalyst illumination and turnover outweigh the touted advantages of replacing heat with light. A demonstration that light can control product selectivity in complex chemical reactions could prove to be transformative. Here, we show how the recently demonstrated plasmonic behaviour of rhodium nanoparticles profoundly improves their already excellent catalytic properties by simultaneously reducing the activation energy and selectively producing a desired but kinetically unfavourable product for the important carbondioxide hydrogenation reaction. Methane is almost exclusively produced when rhodium nanoparticles are mildly illuminated as hot electrons are injected into the anti-bonding orbital of a critical intermediate, while carbon monoxide and methane are equally produced without illumination. The reduced activation energy and super-linear dependence on light intensity cause the unheated photocatalytic methane production rate to exceed the thermocatalytic rate at 350 °C.

Three young northern temperate forest communities in the north-central United States were exposed to factorial combinations of elevated carbondioxide (CO2) and tropospheric ozone (O3) for 11 years. Here, we report results from an extensive sampling of plant biomass and soil conducted at the conclusion of the experiment...

Full Text Available CSIR was commissioned by DME to compile a report on the potential for sequestration of carbondioxide in South Africa in 2004. This report was the first attempt to obtain a picture of this potential. In the paper the main findings of the 2004 report...

Full Text Available Higher concentrations of ammonia (NH3 and carbondioxide (CO2 in animal barns can negatively affect production and health of animals and workers. This paper focuses on measurements of summer concentrations of ammonia (NH3 and carbondioxide (CO2 in a naturally ventilated laying henhouse located at an egg production facility in Bursa region, western Turkey. Also, indoor and ambient environmental conditions such as temperature and relative humidity were measured simultaneously with pollutant gas concentrations. The average NH3 concentrations during summer of 2013 was 8.05 ppm for exhaust and 5.42 ppm for inlet while average CO2 concentration was 732 ppm for exhaust and 625 ppm for inlet throughout summer. The overall minimum, average and maximum values and humidity were obtained as 16.8°C, 24.72°C, and 34.71°C for indoor temperature and 33.64%, 63.71%, and 86.18% for relative humidity. The lowest exhaust concentrations for NH3 and CO2 were 6.98 ppm and 609 ppm, respectively. They were measured in early morning at the maximum diurnal ventilation rate in July 2013 and August 2013. The highest concentrations were 10.58 ppm for NH3 and 904 ppm for CO2 recorded in the afternoon when the ventilation rate was the lowest in June 2013.

Background. In premature infants, maintaining blood partial pressure of carbondioxide (pCO2) value within a narrow range is important to avoid cerebral lesions. The aim of this study was to assess the accuracy of a noninvasive transcutaneous method (TcpCO2), compared to blood partial pressure of carbondioxide (pCO2). Methods. Retrospective observational study in a tertiary neonatal intensive care unit. We analyzed the correlation between blood pCO2 and transcutaneous values and the accuracy between the trends of blood pCO2 and TcpCO2 in all consecutive premature infants born at TcpCO2 and blood pCO2 values. Pearson's R correlation between these values was 0.58. The mean bias was −0.93 kPa with a 95% confidence limit of agreement of −4.05 to +2.16 kPa. Correlation between the trends of TcpCO2 and blood pCO2 values was good in only 39.6%. Conclusions. In premature infants, TcpCO2 was poorly correlated to blood pCO2, with a wide limit of agreement. Furthermore, concordance between trends was equally low. We warn about clinical decision-making on TcpCO2 alone when used as continuous monitoring. PMID:27375901

Transcutaneous oxygen (TcPo2) and carbondioxide (TcPco2) tensions were compared with arterial values in 23 children aged 4 months to 14 years, all requiring some form of respiratory support, but not in shock. Electrodes were placed on the upper chest and were heated to 45 degrees C. For TcPo2 and arterial oxygen (Pao2) a tight linear correlation over the range 6 to 14 kPa was found. Arterial carbondioxide (Paco2) ranged between 2.63 and 6.8 kPa, and over this range a linear regression adequately described the relation of TcPco2 to Paco2. No effects of age were found for the relation between TcPo2 and Pao2. Over a four hour period, the mean ratio TcPo2/Pao2 rose significantly from 0.96 to 1.04, while the mean ratio of TcPco2/Paco2 fell from 1.65 to 1.62. Five children developed superficial burns which were still present at 48 hours. In children who require respiratory support but are not in shock, TcPo2 and TcPco2 bear a constant and predictable relation to Pao2 and Paco2, and can predict arterial values within clinically acceptable tolerances. PMID:3937497

Direct methanol fuel cells have potentially high energy density if the balance of plant and fuel losses can be kept to a minimum. CO 2 accumulation in the fuel tank can lower the efficiency and performance of closed-tank methanol fuel cells. This report discusses the implementation of a passive CO 2 vent fabricated with poly(1-trimethyl silyl propyne) and 1,6-divinylperfluorohexane. The performance of the membrane as a selective vent for carbondioxide in the presence of methanol has been studied at various operating conditions. First, the selectivity of the vent membrane improved with temperature. Second, the activation energy for permeation through the polymer membrane corresponded to diffusion controlled transport of CO 2 and sorption controlled transport for methanol vapor. The activation energy for CO 2 transport through the poly(1-trimethyl silyl propyne) and 1,6-divinylperfluorohexane membrane was less than that for a pure poly(1-trimethyl silyl propyne) membrane. Finally, the polymer had a high selectivity for carbondioxide compared to both liquid and vapor phase methanol.

A variety of methods are currently available to partition water vapor fluxes (into components of transpiration and direct evaporation) and carbondioxide fluxes (into components of photosynthesis and respiration), using chambers, isotopes, and regression modeling approaches. Here, a methodology is presented that accounts for correlations between high-frequency measurements of water vapor (q) and carbondioxide (c) concentrations being influenced by their non-identical source-sink distributions and the relative magnitude of their constituent fluxes. Flux-variance similarity assumptions are applied separately to the stomatal and the non-stomatal exchange, and the flux components are identified by considering the q-c correlation. Water use efficiency for the vegetation, and how it varies with respect to vapor pressure deficit, is the only input needed for this approach that uses standard eddy covariance measurements. The method is demonstrated using data collected over a corn field throughout a growing season. In particular, the research focuses on the partitioning of the water flux with the aim of improving how direct evaporation is handled in soil-vegetation- atmosphere transfer models over the course of wetting and dry-down cycles.

During the course of a fiscal year, Oak Ridge National Laboratory`s CarbonDioxide Information Analysis Center (CDIAC) distributes thousands of specialty publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIACs staff also provides technical responses to specific inquiries related to carbondioxide (CO{sub 2}), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC`s staff. This report provides an account of the activities accomplished by CDIAC during the period October 1, 1991 to September 30, 1992. An organizational overview of CDIAC and its staff is supplemented by a detailed description of inquiries received and CDIAC`s response to those inquiries. As analysis and description of the preparation and distribution of numeric data packages, computer model packages, technical reports, newsletters, fact sheets, specialty publications, and reprints is provided. Comments and descriptions of CDIAC`s information management systems, professional networking, and special bilateral agreements are also described.

During the course of a fiscal year, Oak Ridge National Laboratory`s CarbonDioxide Information Analysis Center (CDIAC) distributes thousands of specially publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIAC`s staff also provides technical responses to specific inquiries related to carbondioxide (CO{sub 2}), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC`s staff. This report provides an account of the activities accomplished by CDIAC during the period October 1, 1990 to September 30, 1991. An organizational overview of CDIAC and its staff is supplemented by a detailed description of inquiries received and CDIAC`s response to those inquiries. An analysis and description of the preparation and distribution of numeric data packages, computer model packages, technical reports, newsletters, factsheets, specially publications, and reprints is provided. Comments and descriptions of CDIAC`s information management systems, professional networking, and special bilateral agreements are also described.

During the course of a fiscal year, Oak Ridge National Laboratory's CarbonDioxide Information Analysis Center (CDIAC) distributes thousands of specially publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIAC's staff also provides technical responses to specific inquiries related to carbondioxide (CO{sub 2}), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC's staff. This report provides an account of the activities accomplished by CDIAC during the period October 1, 1990 to September 30, 1991. An organizational overview of CDIAC and its staff is supplemented by a detailed description of inquiries received and CDIAC's response to those inquiries. An analysis and description of the preparation and distribution of numeric data packages, computer model packages, technical reports, newsletters, factsheets, specially publications, and reprints is provided. Comments and descriptions of CDIAC's information management systems, professional networking, and special bilateral agreements are also described.

The National Aeronautics and Space Administration supported the development of a new vacuum-desorbed regenerative carbondioxide and humidity control technology for use in short duration human spacecraft. The technology was baselined for use in the Orion Crew Exploration Vehicle s Environmental Control and Life Support System (ECLSS). Termed the CarbonDioxide And Moisture Removal Amine Swing-bed (CAMRAS), the unit was developed by Hamilton Sundstrand and has undergone extensive testing at Johnson Space Center. The tests were performed to evaluate performance characteristics under range of operating conditions and human loads expected in future spacecraft applications, as part of maturation to increase its readiness for flight. Early tests, conducted at nominal atmospheric pressure, used human metabolic simulators to generate loads, with later tests making us of human test subjects. During these tests many different test cases were performed, involving from 1 to 6 test subjects, with different activity profiles (sleep, nominal and exercise). These tests were conducted within the airlock portion of a human rated test chamber sized to simulate the Orion cabin free air volume. More recently, a test was completed that integrated the CAMRAS with a simulated suit loop using prototype umbilicals and was conducted at reduced atmospheric pressure and elevated oxygen levels. This paper will describe the facilities and procedures used to conduct these and future tests, and provide a summary of findings.

Phase I concludes with significant progress made towards the SunShot ELEMENTS goals of high energy density, high power density, and high temperature by virtue of a SrO/SrCO3 based material. A detailed exploration of sintering inhibitors has been conducted and relatively stable materials supported by YSZ or SrZO3 have been identified as the leading candidates. In 15 cycle runs using a 3 hour carbonation duration, several materials demonstrated energy densities of roughly 1500 MJ/m3 or greater. The peak power density for the most productive materials consistently exceeded 40 MW/m3—an order of magnitude greater than the SOPO milestone. The team currently has a material demonstrating nearly 1000 MJ/m3 after 100 abbreviated (1 hour carbonation) cycles. A subsequent 8 hour carbonation after the 100 cycle test exhibited over 1500 MJ/m3, which is evidence that the material still has capacity for high storage albeit with slower kinetics. Kinetic carbonation experiments have shown three distinct periods: induction, kinetically-controlled, and finally a diffusion-controlled period. In contrast to thermodynamic equilibrium prediction, higher carbonation temperatures lead to greater conversions over a 1 hour periods, as diffusion of CO2 is more rapid at higher temperatures. A polynomial expression was fit to describe the temperature dependence of the linear kinetically-controlled regime, which does not obey a traditional Arrhenius relationship. Temperature and CO2 partial pressure effects on the induction period were also investigated. The CO2 partial pressure has a strong effect on the reaction progress at high temperatures but is insignificant at temperatures under 900°C. Tomography data for porous SrO/SrCO3 structures at initial stage and after multiple carbonation/decomposition cycles have been obtained. Both 2D slices and 3D reconstructed representations have

for C. ljungdahlii includecarbon monoxide, which can be derived from industrial waste gases or the conversion of recalcitrant biomass to syngas, as well as hydrogen, another syngas component. The finding that carbon and electron flow in C. ljungdahlii can be diverted from the production of acetate to butyrate synthesis is an important step toward the goal of renewable commodity production from carbondioxide with this organism.

Phenomenon of global warming, which is indicated by increasing of earth's surface temperature, is caused by high level of greenhouse gases level in the atmosphere. Carbondioxide, which increases year by year because of high demand of energy, gives the largest contribution in greenhouse gases. One of the most applied solution to mitigate carbondioxide level is post-combustion carbon capture technology. Although the technology can absorb up to 90% of carbondioxide produced, some worries occur that captured carbondioxide that is stored underground will be released over time. Utilizing captured carbondioxide could be a promising solution. Captured carbondioxide can be converted into more valuable material, such as methanol. This research will evaluate the conversion process of captured carbondioxide to methanol, technically and economically. From the research, it is found that technically methanol can be made from captured carbondioxide. Product gives 25.6905 kg/s flow with 99.69% purity of methanol. Economical evaluation of the whole conversion process shows that the process is economically feasible. The capture and conversion process needs 176,101,157.69 per year for total annual cost and can be overcome by revenue gained from methanol product sales.

The International Space Station CarbonDioxide Removal Assembly (CDRA) uses regenerable adsorption technology to remove carbondioxide (COP) from cabin air. Product water vapor measurements from a CDRA test bed at the NASA Marshall Space Flight Center were made using a tunable infrared diode laser differential absorption spectrometer (TILDAS) provided by NASA Glenn Research Center. The TILDAS instrument exceeded all the test specifications, including sensitivity, dynamic range, time response, and unattended operation. During the COP desorption phase, water vapor concentrations as low as 5 ppmv were observed near the peak of CO2 evolution, rising to levels of approx. 40 ppmv at the end of a cycle. Periods of high water concentration (>100 ppmv) were detected and shown to be caused by an experimental artifact. Measured values of total water vapor evolved during a single desorption cycle were as low as 1 mg.

FuelCell Energy, Inc. (FCE), in collaboration with AECOM Corporation (formerly URS Corporation) and Pacific Northwest National Laboratory, has been developing a novel Combined Electric Power and Carbon-dioxide Separation (CEPACS) system. The CEPACS system is based on electrochemical membrane (ECM) technology derived from FCE’s carbonate fuel cell products featuring internal (methane steam) reforming and carrying the trade name of Direct FuelCell®. The unique chemistry of carbonate fuel cells offers an innovative approach for separation of CO2 from existing fossil-fuel power plant exhaust streams (flue gases). The ECM-based CEPACS system has the potential to become a transformational CO2-separation technology by working as two devices in one: it separates the CO2 from the exhaust of other plants such as an existing coal-fired plant and simultaneously produces clean electric power at high efficiency using a supplementary fuel. The development effort was carried out under the U.S. Department of Energy (DOE) cooperative agreement DE-FE0007634. The overall objective of this project was to successfully demonstrate the ability of FCE’s ECM-based CEPACS system technology to separate ≥90% of the CO2 from a simulated Pulverized Coal (PC) power plant flue gas stream and to compress the captured CO2 to a state that can be easily transported for sequestration or beneficial use. In addition, a key objective was to show, through the technical and economic feasibility study and bench scale testing, that the ECM-based CEPACS system is an economical alternative for CO2 capture in PC power plants, and that it meets DOE’s objective related to the incremental cost of electricity (COE) for post-combustion CO2 capture (no more than 35% increase in COE). The project was performed in three budget periods (BP). The specific objective for BP1 was to complete the Preliminary Technical and Economic Feasibility Study

A high efficiency sorbent for CO2 capture was developed by loading polyethylenimine (PEI) on mesoporous carbons which possessed well-developed mesoporous structures and large pore volume. The physicochemical properties of the sorbent were characterized by N2 adsorption/desorption, scanning electron microscopy (SEM), thermal gravimetric analysis (TG) and Fourier transform infrared spectroscopy (FT-IR) techniques followed by testing for CO2 capture. Factors that affected the sorption capacity of the sorbent were studied. The sorbent exhibited extraordinary capture capacity with CO2 concentration ranging from 5% to 80%. The optimal PEI loading was determined to be 65 wt.% with a CO2 sorption capacity of 4.82 mmol-CO2/g-sorbent in 15% CO2/N2 at 75 degrees C, owing to low mass-transfer resistance and a high utilization ratio of the amine compound (63%). Moisture had a promoting effect on the sorption separation of CO2. In addition, the developed sorbent could be regenerated easily at 100 degrees C, and it exhibited excellent regenerability and stability. These results indicate that this PEI-loaded mesoporous carbon sorbent should have a good potential for CO2 capture in the future.

A titanium-based zeolitic imidazolate framework (Ti-ZIF) with high surface area and porous morphology was synthesized and itsefficacy was demonstrated in the synthesis of cyclic carbonates from epoxides and carbondioxide.

Ordered open channels found in two-dimensional covalent organic frameworks (2D COFs) could enable them to adsorb carbondioxide. However, the frameworks' dense layer architecture results in low porosity that has thus far restricted their potential for carbondioxide adsorption. Here we report a

Essential for successful bog restoration is the reestablishment of Sphagnum mosses. High carbondioxide availability has been shown to be of great importance for the growth of Sphagnum mosses. In well-developed Sphagnum bogs large amounts of carbondioxide are produced by (an)aerobic decomposition

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbondioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbondioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed

Full Text Available Rebreathing of carbondioxide caused by incompetent ′cage and disc′ unidirectional valves has been reported earlier. Some manufacturers have changed the design of unidirectional valves to ′flexible leaflets′. We report a series of cases where a deformed membrane leaflet in expiratory unidirectional valves led to rebreathing of carbondioxide.

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbondioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbondioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed.

Heat transfer and pressure drop for carbondioxide, pure and mixed with oil, has the been measured for flow in pipe. The measured heat transfer coefficient for pure carbondioxide is much higher than the value calculated with the Shah correlation. With oil even higher heat transfer coefficient ha...

Molecular Monte Carlo simulations are used to compute the three-phase (hydrate-liquid water-gas) equilibrium lines of methane and carbondioxide hydrates, using the Transferable Potentials for Phase Equilibria model for carbondioxide, the united atom optimized potential for liquid simulations

The use of membrane gas absorption for carbondioxide production from flue gases is discussed with special reference to the combined supply of heat and carbondioxide to greenhouses. Novel absorption liquids are introduced which show an improved performance in terms of system stability and mass

A computationally efficient semi-analytical code, CQUESTRA, has been developed for probabilistic risk assessment and rapid screening of potential sites for geological sequestration of carbondioxide. The rate of dissolution and leakage from a trapped underground pool of carbondioxide is determined. The trapped carbondioxide could be mixed with hydrocarbons and other components to form a buoyant phase. The program considers potential mechanisms for escape from the geological formations such as the movement of the buoyant phase through failed seals in wellbores, the annulus around wellbores and through open fractures in the caprock. Plume animations of dissolved carbondioxide in formation water around the wellbores are provided. Solubility, density and viscosity of the buoyant phase are determined by equations of state. Advection, dispersion, diffusion, buoyancy, aquifer flow rates and local formation fluid pressure are taken into account in the modeling of the carbondioxide movement. Results from a hypothetical example simulation based on data from the Williston basin near Weyburn, Saskatchewan, indicate that this site is potentially a viable candidate for carbondioxide sequestration. Sensitivity analysis of CQUESTRA indicates that criteria such as siting below aquifers with large flow rates and siting in reservoirs having fluid pressure below the pressure of the formations above can promote complete dissolution of the carbondioxide during movement toward the surface, thereby preventing release to the biosphere. Formation of very small carbondioxide bubbles within the fluid in the wellbores can also lead to complete dissolution

In an on-going harmonized ESA/NIVR project, performed by Stork Comprimo and TNO-MEP, the removal of the carbondioxide with membranes is studied. The use of membrane gas absorption for carbondioxide removal is currently hampered by the fact that the commonly used alkanolamines result in leakage

Full Text Available The biogas production from anaerobic digestion is a potential fuel for power generators application, if biogas can be upgraded to the same standards as fossil natural gas by CO2, H2S, and other non-combustible component removal. Microalgae Chlamydomonas sp. has potency to biofix the carbondioxide and can be used as an additional food ingredient. The variations of flow rate and carbondioxide concentration in the process resulting different value of biomass production and carbondioxide biofixation. Biomass production at 40% carbondioxide concentration obtained 5.685 gr/dm3 at 10% carbondioxide concentration obtained 4.892 gr/dm3. The greatest value of carbondioxide absorption occurs at a 40% concentration amounting to 12.09%. The rate of growth and productivity of microalgae tend to rise in 10% and 20% (%v carbondioxide concentration, but began started a constant at 30% and 40% (%v carbondioxide concentration. Biomass production tends to increase in light conditions while a constant in dark conditions. This study used Chlamydomonas sp. as media culture and performed on bubble column and tubular reactor with 6 litres of culture medium at a temperature of 28oC and atmospheric pressure.

Changes in past atmospheric carbondioxide concentrations can be determined by measuring the composition of air trapped in ice cores from Antarctica. So far, the Antarctic Vostok and EPICA Dome C ice cores have provided a composite record of atmospheric carbondioxide levels over the past 650,000...

Research on the driving factors behind carbondioxide emission changes in China can inform better carbon emission reduction policies and help develop a low-carbon economy. As one of important methods, production-theoretical decomposition analysis (PDA) has been widely used to understand these driving factors. To avoid the infeasibility issue in solving the linear programming, this study proposed a modified PDA approach to decompose carbondioxide emission changes into seven drivers. Using 2005–2010 data, the study found that economic development was the largest factor of increasing carbondioxide emissions. The second factor was energy structure (reflecting potential carbon), and the third factor was low energy efficiency. Technological advances, energy intensity reductions, and carbondioxide emission efficiency improvements were the negative driving factors reducing carbondioxide emission growth rates. Carbondioxide emissions and driving factors varied significantly across east, central and west China. - Highlights: • A modified PDA used to decompose carbondioxide emission changes into seven drivers. • Two models were proposed to ameliorate the infeasible occasions. • Economic development was the largest factor of increasing CO 2 emissions in China.